Type-selective benefits of medications in treatment of acute aortic dissection (from the International Registry of Acute Aortic Dissection [IRAD]).

The effects of medications on the outcome of aortic dissection remain poorly understood. We sought to address this by analyzing the International Registry of Acute Aortic Dissection (IRAD) global registry database. A total of 1,301 patients with acute aortic dissection (722 with type A and 579 with type B) with information on their medications at discharge and followed for ≤5 years were analyzed for the effects of the medications on mortality. The initial univariate analysis showed that use of ß blockers was associated with improved survival in all patients (p = 0.03), in patients with type A overall (p = 0.02), and in patients with type A who received surgery (p = 0.006). The analysis also showed that use of calcium channel blockers was associated with improved survival in patients with type B overall (p = 0.02) and in patients with type B receiving medical management (p = 0.03). Multivariate models also showed that the use of ß blockers was associated with improved survival in those with type A undergoing surgery (odds ratio 0.47, 95% confidence interval 0.25 to 0.90, p = 0.02) and the use of calcium channel blockers was associated with improved survival in patients with type B medically treated patients (odds ratio 0.55, 95% confidence interval 0.35 to 0.88, p = 0.01). In conclusion, the present study showed that use of ß blockers was associated with improved outcome in all patients and in type A patients (overall as well as in those managed surgically). In contrast, use of calcium channel blockers was associated with improved survival selectively in those with type B (overall and in those treated medically). The use of angiotensin-converting enzyme inhibitors did not show association with mortality.

Correlates of delayed recognition and treatment of acute type A aortic dissection: the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: In acute aortic dissection, delays exist between presentation and diagnosis and, once diagnosed, definitive treatment. This study aimed to define the variables associated with these delays. METHODS AND RESULTS: Acute aortic dissection patients enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and January 2007 were evaluated for factors contributing to delays in presentation to diagnosis and in diagnosis to surgery. Multiple linear regression was performed to determine relative delay time ratios (DTRs) for individual correlates. The median time from arrival at the emergency department to diagnosis was 4.3 hours (quartile 1-3, 1.5-24 hours; n=894 patients) and from diagnosis to surgery was 4.3 hours (quartile 1-3, 2.4-24 hours; n=751). Delays in acute aortic dissection diagnosis occurred in female patients; those with atypical symptoms that were not abrupt or did not include chest, back, or any pain; patients with an absence of pulse deficit or hypotension; or those who initially presented to a nontertiary care hospital (all P<0.05). The largest relative DTRs were for fever (DTR=5.11; P<0.001) and transfer from nontertiary hospital (DTR=3.34; P<0.001). Delay in time from diagnosis to surgery was associated with a history of previous cardiac surgery, presentation without abrupt or any pain, and initial presentation to a nontertiary care hospital (all P<0.001). The strongest factors associated with operative delay were prolonged time from presentation to diagnosis (DTR=1.35; P<0.001), race other than white (DTR=2.25; P<0.001), and history of coronary artery bypass surgery (DTR=2.81; P<0.001). CONCLUSIONS: Improved physician awareness of atypical presentations and prompt transport of acute aortic dissection patients could reduce crucial time variables.

Sensitivity of the aortic dissection detection risk score, a novel guideline-based tool for identification of acute aortic dissection at initial presentation: results from the international registry of acute aortic dissection.

BACKGROUND: In 2010, the American Heart Association and American College of Cardiology released guidelines for the diagnosis and management of patients with thoracic aortic disease, which identified high-risk clinical features to assist in the early detection of acute aortic dissection. The sensitivity of these risk markers has not been validated. METHODS AND RESULTS: We examined patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2009. The number of patients with confirmed acute aortic dissection who presented with 1 or more of 12 proposed clinical risk markers was determined. An aortic dissection detection (ADD) risk score of 0 to 3 was calculated on the basis of the number of risk categories (high-risk predisposing conditions, high-risk pain features, high-risk examination features) in which patients met criteria. The ADD risk score was tested for sensitivity. Of 2538 patients with acute aortic dissection, 2430 (95.7%) were identified by 1 or more of 12 proposed clinical risk markers. With the use of the ADD risk score, 108 patients (4.3%) were identified as low risk (ADD score 0), 927 patients (36.5%) were intermediate risk (ADD score 1), and 1503 patients (59.2%) were high risk (ADD score 2 or 3). Among 108 patients with no clinical risk markers present (ADD score 0), 72 had chest x-rays recorded, of which 35 (48.6%) demonstrated a widened mediastinum. CONCLUSIONS: The clinical risk markers proposed in the 2010 thoracic aortic disease guidelines and their application as part of the ADD risk score comprise a highly sensitive clinical tool for the detection of acute aortic dissection.

The role of preoperative coronary angiography in the setting of type A acute aortic dissection: insights from the International Registry of Acute Aortic Dissection.

BACKGROUND: Performing preoperative coronary angiography (CA) before surgical repair of a type A acute aortic dissection (TA-AAD) remains controversial. Although the information provided by CA may be useful in planning the surgical approach, the potential delay to surgery and complications of CA may confer added risk of death before definitive repair of the aorta. METHODS: We analyzed 1,343 patients from January 27, 1996, to May 3, 2010, with TA-AAD from the International Registry of Acute Aortic Dissection who underwent surgical or endovascular repair during the index hospitalization, with (n = 156) or without (n = 1,187) preoperative CA. The main outcomes measured were in-hospital complications and in-hospital and long-term mortality. RESULTS: Patients who underwent preoperative CA were more likely to have a history of atherosclerosis and present with electrocardiographic signs of myocardial ischemia/infarction. In the preoperative CA group, significant delays from the onset of symptoms to the time of surgery occurred. In-hospital postoperative complications and mortality rates were largely similar between the 2 groups. On multivariable logistic regression analysis, preoperative CA had no significant effect on in-hospital risk-adjusted mortality when compared to the validated International Registry of Acute Aortic Dissection risk score. Long-term mortality was similar between patients receiving preoperative CA and those who did not; long-term rehospitalization rates were higher, although largely insignificantly, among preoperative CA recipients through 5 years of follow-up. CONCLUSIONS: Preoperative CA is infrequently performed on patients with TA-AAD, except, occasionally, on patients at high risk for myocardial ischemia. When performed, preoperative CA was not associated with any significant changes in in-hospital and long-term mortality.

Ascending thoracic aorta dimension and outcomes in acute type B dissection (from the International Registry of Acute Aortic Dissection [IRAD]).

It is not well known if the size of the ascending thoracic aorta at presentation predicts features of presentation, management, and outcomes in patients with acute type B aortic dissection. The International Registry of Acute Aortic Dissection (IRAD) database was queried for all patients with acute type B dissection who had documentation of ascending thoracic aortic size at time of presentation. Patients were categorized according to ascending thoracic aortic diameters ≤4.0, 4.1 to 4.5, and ≥4.6 cm. Four hundred eighteen patients met inclusion criteria; 291 patients (69.6%) were men with a mean age of 63.2 ± 13.5 years. Ascending thoracic aortic diameter ≤4.0 cm was noted in 250 patients (59.8%), 4.1 to 4.5 cm in 105 patients (25.1%), and ≥4.6 cm in 63 patients (15.1%). Patients with an ascending thoracic aortic diameter ≥4.6 cm were more likely to be men (p = 0.01) and have Marfan syndrome (p <0.001) and known bicuspid aortic valve disease (p = 0.003). In patients with an ascending thoracic aorta ≥4.1 cm, there was an increased incidence of surgical intervention (p = 0.013). In those with an ascending thoracic aorta ≥4.6 cm, the root, ascending aorta, arch, and aortic valve were more often involved in surgical repair. Patients with an ascending thoracic aorta ≤4.0 were more likely to have endovascular therapy than those with larger ascending thoracic aortas (p = 0.009). There was no difference in overall mortality or cause of death. In conclusion, ascending thoracic aortic enlargement in patients with acute type B aortic dissection is common. Although its presence does not appear to predict an increased risk of mortality, it is associated with more frequent open surgical intervention that often involves replacement of the proximal aorta. Those with smaller proximal aortas are more likely to receive endovascular therapy.

Importance of refractory pain and hypertension in acute type B aortic dissection: insights from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: In patients with acute type B aortic dissection, presence of recurrent or refractory pain and/or refractory hypertension on medical therapy is sometimes used as an indication for invasive treatment. The International Registry of Acute Aortic Dissection (IRAD) was used to investigate the impact of refractory pain and/or refractory hypertension on the outcomes of acute type B aortic dissection. METHODS AND RESULTS: Three hundred sixty-five patients affected by uncomplicated acute type B aortic dissection, enrolled in IRAD from 1996 to 2004, were categorized according to risk profile into 2 groups. Patients with recurrent and/or refractory pain or refractory hypertension (group I; n=69) and patients without clinical complications at presentation (group II; n=296) were compared. "High-risk" patients with classic complications were excluded from this analysis. The overall in-hospital mortality was 6.5% and was increased in group I compared with group II (17.4% versus 4.0%; P=0.0003). The in-hospital mortality after medical management was significantly increased in group I compared with group II (35.6% versus 1.5%; P=0.0003). Mortality rates after surgical (20% versus 28%; P=0.74) or endovascular management (3.7% versus 9.1%; P=0.50) did not differ significantly between group I and group II, respectively. A multivariable logistic regression model confirmed that recurrent and/or refractory pain or refractory hypertension was a predictor of in-hospital mortality (odds ratio, 3.31; 95% confidence interval, 1.04 to 10.45; P=0.041). CONCLUSIONS: Recurrent pain and refractory hypertension appeared as clinical signs associated with increased in-hospital mortality, particularly when managed medically. These observations suggest that aortic intervention, such as via an endovascular approach, may be indicated in this intermediate-risk group.

Role of age in acute type A aortic dissection outcome: report from the International Registry of Acute Aortic Dissection (IRAD).

OBJECTIVE: The increasing life expectancy of the population will likely be accompanied by a rise in the incidence of acute type A aortic dissection. However, because of an increased risk of cardiac surgery in an elderly population, it is important to define when, if at all, the risks of aortic repair outweigh the risk of death from unoperated type A aortic dissection. METHODS: We analyzed 936 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2004. Patients with type A aortic dissection were categorized according to patient age by decade and by surgical versus medical management, and outcomes of both management types were investigated in the different age groups. RESULTS: The rate of surgical aortic repair decreased progressively with age, whereas surgical mortality significantly increased with age. Age 70 years or more was an independent predictor for mortality (38.2% vs 26.0%; P < .0001, odds ratio 1.73). The in-hospital mortality rate was significantly lower after surgical management compared with medical management until the age of 80 years. For patients aged 80 to 90 years, the in-hospital mortality appeared to be lower after surgical management (37.9% vs 55.2%; P = .188); however, this failed to reach clinical significance owing to the limited patient number in this age group. CONCLUSIONS: Although the surgical mortality significantly increased with increased age, surgical management was still associated with significantly lower in-hospital mortality rates compared with medical management until the age of 80 years. Surgery may decrease the in-hospital mortality rate for octogenarians with type A aortic dissection and might be considered in all patients with type A aortic dissection regardless of age.

Characteristics and in-hospital outcomes of patients with cardiac tamponade complicating type A acute aortic dissection.

Cardiac tamponade (TMP) is a life-threatening complication of acute type A aortic dissection (AAD). The purpose of this study was to assess the clinical characteristics and in-hospital outcomes of TMP in the setting of AAD on the basis of the findings in the large cohort of the International Registry of Acute Aortic Dissection (IRAD). Six hundred seventy-four patients (mean age 61.8 +/- 14.2 years) with AAD in IRAD were studied. TMP was suspected on clinical grounds and confirmed by diagnostic imaging. Univariate testing was followed by multivariate logistic regression analysis to determine the association of TMP. TMP was detected in 126 patients with AAD (18.7%). Age did not differ between patients with and without TMP. Those with TMP less often had previous cardiac surgery (7.0% vs 17.1%, p = 0.007). Syncope (37.8% vs 13.7%, p <0.0001) and altered mental status (31.2% vs 10.6%, p <0.0001) were more common in patients with AAD with TMP than without TMP. Patients with TMP were more likely to have widened mediastina on chest x-ray (72.6% vs 60.3%, p = 0.02) and to have periaortic hematomas (44.7% vs 21.2%, p <0.0001). In-hospital outcomes were significantly worse in patients with TMP. The mortality of patients with TMP remained significantly higher, even after adjustment for baseline clinical characteristics (p <0.001). On logistic regression, altered mental status, hypotension, and early mortality were identified as independent correlates of TMP. In conclusion, TMP is not uncommon in patients with AAD. Syncope, altered mental status, and a widened mediastinum on chest x-ray on presentation suggest TMP, the presence of which warrants urgent operative therapy to improve outcome.

Geographic differences in clinical presentation, treatment, and outcomes in type A acute aortic dissection (from the International Registry of Acute Aortic Dissection).

Although several studies have provided robust evidence about global differences for several cardiovascular emergencies, such as myocardial infarction and stroke, data were limited for aortic disease. The aim was to explore geographic variation in type A acute aortic dissection (TA-AAD) in a large group of consecutive patients. Patients (n = 615) from the IRAD with TA-AAD were studied with respect to presenting symptoms and signs, diagnosis, management, and outcomes in Europe versus North America. Compared with Europeans, North Americans were more likely to be older and present with atypical features and without many of the classic chest X-ray findings of AAD. In the North American cohort, electrocardiographic findings showed higher rates of nonspecific ST changes and a trend toward ST-elevation or new myocardial infarction (North Americans vs Europeans 7.9% vs 4.4%; p = 0.09). Use of imaging studies to confirm the diagnosis of AAD varied between North American and European centers. North American centers performed an average of 1.6 imaging studies compared with 1.8 in the European group (p = 0.002). Furthermore, they were significantly less likely to use computed tomography and significantly more likely to use transesophageal examination as part of the overall diagnostic algorithm. Compared with Europeans, TA-AAD occurred at smaller aortic diameters and there was a substantial delay to presentation and diagnosis in North Americans. No significant differences for early mortality rates were observed between the 2 groups. In conclusion, geographic differences in presentation and initial management were highlighted, but this did not translate into a difference in early mortality.

Complicated acute type B dissection: is surgery still the best option?: a report from the International Registry of Acute Aortic Dissection.

OBJECTIVES: Impact on survival of different treatment strategies was analyzed in 571 patients with acute type B aortic dissection enrolled from 1996 to 2005 in the International Registry of Acute Aortic Dissection. BACKGROUND: The optimal treatment for acute type B dissection is still a matter of debate. METHODS: Information on 290 clinical variables were compared, including demographics; medical history; clinical presentation; physical findings; imaging studies; details of medical, surgical, and endovascular management; in-hospital clinical events; and in-hospital mortality. RESULTS: Of the 571 patients with acute type B aortic dissection, 390 (68.3%) were treated medically, 59 (10.3%) with standard open surgery and 66 (11.6%) with an endovascular approach. Patients who underwent emergency endovascular or open surgery were younger (mean age 58.8 years, p < 0.001) than their counterparts treated conservatively, and had male preponderance and hypertension in 76.9%. Patients submitted to surgery presented with a wider aortic diameter than patients treated by interventional techniques or by medical therapy (5.36 +/- 1.7 cm vs. 4.62 +/- 1.4 cm vs. 4.47 +/- 1.4 cm, p = 0.003). In-hospital complications occurred in 20% of patients subjected to endovascular technique and in 40% of patients after open surgical repair. In-hospital mortality was significantly higher after open surgery (33.9%) than after endovascular treatment (10.6%, p = 0.002). After propensity and multivariable adjustment, open surgical repair was associated with an independent increased risk of in-hospital mortality (odds ratio: 3.41, 95% confidence interval: 1.00 to 11.67, p = 0.05). CONCLUSIONS: In the International Registry of Acute Aortic Dissection, the less invasive nature of endovascular treatment seems to provide better in-hospital survival in patients with acute type B dissection; larger randomized trials or comprehensive registries are needed to access impact on outcomes.

Acute abdominal aortic dissection: insight from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: Isolated acute dissection of the abdominal aorta is an unusual event that may present with several different clinical scenarios. Because its incidence is low, the natural history is unknown. We report data from the International Registry of Acute Aortic Dissection (IRAD), the largest group of patients treated for acute aortic dissections. The aim of this study was to identify clinical characteristics, therapeutic approaches, risk factors for mortality, in-hospital outcome, and long-term results of this cohort, thus clarifying its natural history. METHODS: A comprehensive analysis of 290 clinical variables on 18 patients affected by isolated acute abdominal aortic dissection (IAAAD) was performed. Among 1417 patients enrolled in the IRAD from 1996 to 2003, 532 (37.5%) had an acute type B dissection, of which 18 (1.3%) had an IAAAD. Theor mean age was 67.7 +/- 13.3 years, with a male predominance (n = 12, 67%). Aortic aneurysms pre-existed in 5 patients (28%). IAAAD was iatrogenic in 2 cases (11%). RESULTS: Compared with patients with type B aortic dissections, abdominal pain, mesenteric ischemia or infarction, limb ischemia, and hypotension as initial clinical signs were significantly more frequent in patients with IAAAD, whereas chest pain was more typical in patients with type B dissections. No neurologic symptoms, such as ischemic spinal cord damage or ischemic peripheral neuropathy, occurred in the IAAAD cohort. The 18 IAAAD patients were medically, surgically, or percutaneously managed in 12 (66.6%), five (27.8%), and one (5.6%) cases, respectively. The overall in-hospital mortality rate was 5.6% (n = 1). The patient who died was medically managed. No deaths were reported among patients who underwent surgery or had an endovascular procedure, irrespective of their preoperative status. A mean follow-up of 5 years (range, 1 month to 9 years) was completed for 71% (12 of 17) of the patients. Four patients (33.3%) died during the 9-year follow-up period. Overall survival was 93.3% +/- 12.6% at 1 year and 73.3% +/- 27.2% at 5 years. All patients who died during the follow-up period had in-hospital medical management (P = .04). CONCLUSIONS: IAAAD is a condition that may present differently compared with classic type B aortic dissections. IAAAD patients treated with surgical or endovascular procedures had a lower unadjusted in-hospital and long-term mortality rate compared with medically managed patients. On the basis of the present natural history report, continued surveillance appears mandatory. To improve the life expectancy of patients with IAAAD, aggressive surgical or endovascular management seems justified.

Acute type B aortic dissection: does aortic arch involvement affect management and outcomes? Insights from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: Stanford Type B acute aortic dissection (TB-AAD) spares the ascending aorta and is optimally managed with medical therapy in the absence of complications. However, the treatment of TB-AAD with aortic arch involvement (AAI) remains an unresolved issue. METHODS AND RESULTS: We examined 498 patients with TB-AAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier mortality curves were constructed and multivariate regression models were performed to identify independent predictors of AAI and to evaluate whether AAI was an independent predictor of follow-up mortality. We found that 371 (74.5%) patients with TB-AAD did not have AAI versus 127 (25.5%) with AAI. Independent predictors of AAI were a history of previous aortic surgery (OR 3.4; 95% CI, 1.6 to 7.6; P=0.002), absence of back pain (OR 1.6; 95% CI, 1.1 to 2.5; P=0.05), and any pulse deficit (1.9; 95% CI, 1.1 to 3.3, P=0.03). Mortality for patients without AAI was 9.4%+/-4.3% and 21.0%+/-6.9% at 1 and 3 years versus 9.2%+/-7.7% and 19.9%+/-11.1% with AAI, respectively (mean follow-up overall, 2.3 years, log rank P=0.82). AAI was not an independent predictor of long-term mortality. CONCLUSIONS: Patients with TB-AAD and aortic arch involvement do not differ with regards to mortality at 3 years. Whether or not AAI involvement impacts other measures of morbidity such as freedom from operation or endovascular intervention deserves further study.

Aortic diameter >or = 5.5 cm is not a good predictor of type A aortic dissection: observations from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: Studies of aortic aneurysm patients have shown that the risk of rupture increases with aortic size. However, few studies of acute aortic dissection patients and aortic size exist. We used data from our registry of acute aortic dissection patients to better understand the relationship between aortic diameter and type A dissection. METHODS AND RESULTS: We examined 591 type A dissection patients enrolled in the International Registry of Acute Aortic Dissection between 1996 and 2005 (mean age, 60.8 years). Maximum aortic diameters averaged 5.3 cm; 349 (59%) patients had aortic diameters <5.5 cm and 229 (40%) patients had aortic diameters <5.0 cm. Independent predictors of dissection at smaller diameters (<5.5 cm) included a history of hypertension (odds ratio, 2.17; 95% confidence interval, 1.03 to 4.57; P=0.04), radiating pain (odds ratio, 2.08; 95% confidence interval, 1.08 to 4.0; P=0.03), and increasing age (odds ratio, 1.03; 95% confidence interval, 1.00 to 1.05; P=0.03). Marfan syndrome patients were more likely to dissect at larger diameters (odds ratio, 14.3; 95% confidence interval, 2.7 to 100; P=0.002). Mortality (27% of patients) was not related to aortic size. CONCLUSIONS: The majority of patients with acute type A acute aortic dissection present with aortic diameters <5.5 cm and thus do not fall within current guidelines for elective aneurysm surgery. Methods other than size measurement of the ascending aorta are needed to identify patients at risk for dissection.

Partial thrombosis of the false lumen in patients with acute type B aortic dissection.

BACKGROUND: Patency or thrombosis of the false lumen in type B acute aortic dissection has been found to predict outcomes. The prognostic implications of partial thrombosis of the false lumen have not yet been elucidated. METHODS: We examined 201 patients with type B acute aortic dissection who were enrolled in the International Registry of Acute Aortic Dissection between 1996 and 2003 and who survived to hospital discharge. Kaplan-Meier mortality curves were stratified according to the status of the false lumen (patent, partial thrombosis, or complete thrombosis) as determined during the index hospitalization. Cox proportional-hazards analysis was performed to identify independent predictors of death. RESULTS: During the index hospitalization, 114 patients (56.7%) had a patent false lumen, 68 patients (33.8%) had partial thrombosis of the false lumen, and 19 (9.5%) had complete thrombosis of the false lumen. The mean (+/-SD) 3-year mortality rate for patients with a patent false lumen was 13.7+/-7.1%, for those with partial thrombosis was 31.6+/-12.4%, and for those with complete thrombosis was 22.6+/-22.6% (median follow-up, 2.8 years; P=0.003 by the log-rank test). Independent predictors of postdischarge mortality were partial thrombosis of the false lumen (relative risk, 2.69; 95% confidence interval [CI], 1.45 to 4.98; P=0.002), a history of aortic aneurysm (relative risk, 2.05; 95% CI, 1.07 to 3.93; P=0.03), and a history of atherosclerosis (relative risk, 1.87; 95% CI, 1.01 to 3.47; P=0.05). CONCLUSIONS: Mortality is high after discharge from the hospital among patients with type B acute aortic dissection. Partial thrombosis of the false lumen, as compared with complete patency, is a significant independent predictor of postdischarge mortality in these patients.

Prognostic role of transesophageal echocardiography in acute type A aortic dissection.

BACKGROUND: Acute type A aortic dissection (AAD) remains a highly lethal entity for which emergent surgical correction is standard care. Prior studies have identified specific clinical findings as being predictive of outcome. The prognostic significance of specific findings on imaging studies is less well described. We sought to identify the prognostic value of transesophageal echocardiography (TEE) in medically and surgically treated patients with AAD. METHODS: We studied 522 AAD patients enrolled over 6 years in the International Registry of Acute Aortic Dissection who underwent TEE. Multivariate analysis identified independent associations of inhospital mortality, first using clinical variables (model 1), after which TEE data were added to build a final model (model 2). RESULTS: Inhospital mortality was 28.7%. Transesophageal echocardiographic evidences of pericardial effusion (P = .04), tamponade (P < .01), periaortic hematoma (P = .02), and patent false lumen (P = .08) were more frequent in nonsurvivors. Dilated ascending aorta (P = .03), dissection localized to the ascending aorta (P = .02), and thrombosed false lumen (P = .08) were less common in nonsurvivors. Model 1 identified age > or = 70 years, any pulse deficit, renal failure, and hypotension/shock as independent predictors of death. Model 2 identified dissection flap confined to ascending aorta (odds ratio 0.2, 95% CI 0.1-0.6) and complete thrombosis of false lumen (odds ratio 0.15, 95% CI 0.03-0.86) as protective. In the medically treated group, mortality was 31% for subjects with a partially or completely thrombosed false lumen versus 66% in the presence of a patent false lumen. CONCLUSIONS: Transesophageal echocardiography provides prognostic information in AAD beyond that provided by clinical risk variables.

The duration of anticoagulation bridging therapy in clinical practice may significantly exceed that observed in clinical trials.

BACKGROUND: Clinical trials involving frequent, standardized monitoring of the international normalized ratio (INR) demonstrated that a short course of low-molecular-weight-heparin (LMWH) can successfully bridge patients to oral anticoagulation. However, rigidly performed INR testing is often not feasible in the outpatient setting in actual clinical practice. The purpose of this study was to determine if the anticoagulation results of clinical trials of LMWH bridging therapy are also achieved in a single-center clinical practice setting. METHODS: We conducted a retrospective analysis of 100 patients initiating warfarin while receiving LMWH under the care of a university-based anticoagulation management service. RESULTS: Mean patient age was 56.1 +/- 16.3 years. The commonest indications for anticoagulation were venous thrombosis (57%) and atrial fibrillation (25%). Mean initial warfarin dose was 5.1 +/- 1.8 mg/day; 30% of patients received antiplatelet therapy. The mean total duration of LMWH therapy was 12.0 +/- 8.2 days, of which 9.8 +/- 8.0 days (median 7.5 days; interquartile range 4.3-13.0 days) occurred in the outpatient setting. Forty-one percent of patients received outpatient LMWH for < 7 days, 40% for 7-14 days, and 19% for > 14 days. A mean of 3.9 +/- 2.0 INRs were performed during LMWH therapy. Complications included 11 minor and 1 major bleeding episodes and 1 thrombotic event. CONCLUSIONS: The duration of LMWH bridging therapy in practice may be significantly greater than previously reported in clinical trials, and the incidence of patients requiring prolonged (>14 days) LMWH therapy is relatively high. Outpatient LMWH as employed in clinical practice safely bridges patients to oral anticoagulation. Strategies to shorten the duration of LMWH therapy are needed and are likely to improve clinical outcomes and reduce health care expenses. In prospective clinical trials low-molecular-weight-heparin (LMWH) has proven effective in transitioning patients with venous thromboembolic disease to therapeutic warfarin anticoagulation. However, it is unknown if the anticoagulation results obtained in these trials, which involved rigidly performed anticoagulation monitoring, are achieved in standard clinical practice involving patients with a variety of indications for anticoagulation. We conducted a retrospective analysis of 100 patients initiating warfarin while receiving LMWH under the management of a university-based anticoagulation management service. The mean total duration of LMWH therapy was 12.0 +/- 8.2 days, of which 9.8 +/- 8.0 days (median 7.5 days; interquartile range 4.3-13.0 days) occurred in the outpatient setting. Forty-one percent of patients received outpatient LMWH for <7 days, 40% for 7-14 days, and 19% for >14 days. We conclude that the duration of LMWH bridging therapy in practice may be significantly greater than previously reported in clinical trials, and the incidence of patients requiring prolonged (>14 days) LMWH therapy is relatively high.

Simple risk models to predict surgical mortality in acute type A aortic dissection: the International Registry of Acute Aortic Dissection score.

BACKGROUND: Surgical mortality for acute type A aortic dissection is frequently related to preoperative clinical conditions. We report a predictive score to identify risk of death that may be helpful to assist surgeons who are considering whether to proceed with surgical correction in the case of patients in extreme clinical risk. METHODS: Surgical outcome of 682 patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2003 was analyzed. Two different models were used. The initial model included only preoperative variables such as demographics, history, symptoms, signs, and diagnostic methods (model 1). The second model also tested intraoperative hemodynamic and surgical variables (model 2). A bedside risk prediction tool to predict operative mortality in individual patients was developed. RESULTS: The overall in-hospital surgical mortality was 23.9%. Independent preoperative predictors of mortality in model 1 were age greater than 70 years, prior cardiac surgery, hypotension (systolic blood pressure less than 100 mm Hg) or shock at presentation, migrating pain, cardiac tamponade, any pulse deficit, and electrocardiogram with findings of myocardial ischemia or infarction. In model 2, other predictors of surgical death were intraoperative hypotension, a right ventricle dysfunction at surgery, and a necessity to perform coronary revascularization. An independent predictor for favorable surgical outcome was right hemiarch replacement. CONCLUSIONS: Surgery in unstable patients with acute type A aortic dissection can be highly unsuccessful. The International Registry of Acute Aortic Dissection risk models predict in-hospital mortality using a multivariable risk prediction tool, useful for surgeons and patients as they consider their surgical risk and the pros and cons of embarking on high-risk surgery.

Long-term survival in patients presenting with type B acute aortic dissection: insights from the International Registry of Acute Aortic Dissection.

BACKGROUND: Follow-up survival studies in patients with acute type B aortic dissection have been restricted to a small number of patients in single centers. We used data from a contemporary registry of acute type B aortic dissection to better understand factors associated with adverse long-term survival. METHODS AND RESULTS: We examined 242 consecutive patients discharged alive with acute type B aortic dissection enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier survival curves were constructed, and Cox proportional hazards analysis was performed to identify independent predictors of follow-up mortality. Three-year survival for patients treated medically, surgically, or with endovascular therapy was 77.6+/-6.6%, 82.8+/-18.9%, and 76.2+/-25.2%, respectively (median follow-up 2.3 years, log-rank P=0.61). Independent predictors of follow-up mortality included female gender (hazard ratio [HR],1.99; 95% confidence interval [CI], 1.07 to 3.71; P=0.03), a history of prior aortic aneurysm (HR, 2.17; 95% CI, 1.03 to 4.59; P=0.04), a history of atherosclerosis (HR, 2.48; 95% CI, 1.32 to 4.66; P<0.01), in-hospital renal failure (HR, 2.55; 95% CI, 1.15 to 5.63; P=0.02), pleural effusion on chest radiograph (HR, 2.56; 95% CI, 1.18 to 5.58; P=0.02), and in-hospital hypotension/shock (HR, 12.5; 95% CI, 3.24 to 48.21; P<0.01). CONCLUSIONS: Contemporary follow-up mortality in patients who survive to hospital discharge with acute type B aortic dissection is high, approaching 1 in every 4 patients at 3 years. Current treatment and follow-up surveillance require further study to better understand and optimize care for patients with this complex disease.

Acute limb ischemia associated with type B aortic dissection: clinical relevance and therapy.

BACKGROUND: The goal of the current study is to characterize the presentation, therapy, and outcomes of acute limb ischemia (ALI) associated with type B aortic dissection (AoD). METHODS: The prospective/retrospective International Registry for Acute Aortic Dissection (IRAD) database and a single institutional database were queried for all patients with type B AoD from 1996 to 2002. Univariate and multivariate statistics were used to delineate factors associated with morbidity and mortality outcomes. RESULTS: According to the IRAD data (n = 458), the mean age of patients was 64 years, and 70% were men. The overall mortality was 12%; of these, 6% had ALI. Pulse (3-fold) and neurologic deficits (5-fold) were more common in those with ALI (P < .001). Endovascular, but not surgical therapy, was more commonly performed in patients with ALI compared with those without ALI (31% vs 10%, P = .004). No difference in age, race, gender, or origin of dissection was observed. ALI was associated with acute renal failure (odds ratio [OR] = 2.7; 95% confidence interval [CI] 1.1-7.1; P = .048) and acute mesenteric ischemia/infarction (OR = 6.9; 95% CI 2.5-20; P < .001). Adjusting for patient characteristics, ALI was associated with death (3.5; 95% CI 1.1-10; P = .02). The single institution analysis revealed similar patient demographics and mortality in 93 AoD patients, of whom 28 had ALI. Aortic fenestration or aorto-iliac stenting was the primary therapy in 93%; surgical bypass was used in 7%. Limb salvage was 93% in those with ALI at a mean of 18 months follow-up. The number of organ systems with malperfusion was 2-fold higher at aortography than suspected preprocedure (P = .002). By stepwise regression modeling, mortality was greater in those not taking a beta-blocker (OR = 19; 95% CI 3.1-111; P = .001). CONCLUSIONS: ALI secondary to AoD is predictive of death and visceral ischemia. Endovascular therapy confers excellent limb salvage and allows diagnosis of unsuspected visceral ischemia.

Long-term survival in patients presenting with type A acute aortic dissection: insights from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: Earlier studies evaluating long-term survival in type A acute aortic dissection (TA-AAD) have been restricted to a small number of patients in single center experiences. We used data from a contemporary, multi-center international registry of TA-AAD patients to better understand factors associated with long-term survival. METHODS AND RESULTS: We examined 303 consecutive patients with TA-AAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. We included patients who were discharged alive and had documented clinical follow-up data. Kaplan-Meier survival curves were constructed to depict cumulative survival in patients from date of hospital discharge. Stepwise Cox proportional hazards analysis was performed to identify independent predictors of follow-up mortality. We found that 273 (90.1%) patients had been managed surgically and 30 (9.9%) were managed medically. Patients who were dead at follow-up were more likely to be older (63.9 versus 58.4 years, P=0.007) and to have had previous cardiac surgery (23.9% versus 10.6%, P=0.01). Survival for patients treated with surgery was 96.1%+/-2.4% and 90.5%+/-3.9% at 1 and 3 years versus 88.6%+/-12.2% and 68.7%+/-19.8% without surgery (mean follow-up overall, 2.8 years, log rank P=0.009). Multivariate analysis identified a history of atherosclerosis (relative risk (RR), 2.17; 95% confidence interval [CI], 1.08 to 4.37; P=0.03) and previous cardiac surgery (RR, 2.54; 95% CI, 1.16 to 5.57; P=0.02) as significant, independent predictors of follow-up mortality. CONCLUSIONS: Contemporary 1- and 3-year survival in patients with TA-AAD treated surgically are excellent. Independent predictors of survival during the follow-up period do not appear to be influenced by in-hospital risks but rather preexisting comorbidities.