The Clinical Impact of Imaging Surveillance and Clinic Visit Frequency after Acute Aortic Dissection.

BACKGROUND: Guidelines recommend frequent follow-up after acute aortic dissection (AAD), but optimal rates of follow-up are not clear. METHODS: We examined rates of imaging and clinic visits in 267 individuals surviving AAD during recommended intervals (≤1, > 1-3, > 3-6, > 6-12 months, then annually), frequency of adverse imaging findings, and the relationship between follow-up and mortality. RESULTS: Type A and B AAD were noted in 46 and 54% of patients, respectively. Mean follow-up was 54.7 ± 13.3 months, with 52 deaths. Adverse imaging findings peaked at 6 to 12 months (5.6%), but rarely resulted in an intervention (3.4% peak at 6-12 months). Compared with those with less frequent imaging, patients with imaging for 33 to 66% of intervals (p = 0.22) or ≥66% of intervals (p = 0.77) had similar adjusted survival. In comparison to patients with fewer clinic visits, those with visits in 33 to 66% of intervals experienced lower adjusted mortality (hazards ratio: 0.47, 95% confidence interval: 0.23-0.97, p = 0.04), with no difference seen in those with ≥66% (vs. < 33%) interval visits (p = 0.47). Imaging at 6 to 12 months (vs. none) was associated with decreased adjusted mortality (hazards ratio: 0.50, 95% confidence interval: 0.27-0.91, p = 0.02), while imaging during other intervals, or clinic visits during any specific intervals, was not associated with a difference in mortality (p > 0.05 for each). CONCLUSIONS: Adverse imaging findings following AAD are common, but rarely require prompt intervention. Patients with the lowest and highest rates of clinic visits experienced increased mortality. While the overall rate of surveillance imaging did not correlate with mortality, adverse imaging findings and related interventions peaked at 6 to 12 months after AAD, and imaging during this time was associated with improved survival.

Patients With Type A Acute Aortic Dissection Presenting With an Abnormal Electrocardiogram.

BACKGROUND: The electrocardiogram (ECG) is often used in the diagnosis of patients presenting with chest pain to emergency departments. Because chest pain is a common manifestation of type A acute aortic dissection (TAAAD), ECGs are obtained in much of this population. We evaluated the effect of particular ECG patterns on the diagnosis and treatment of TAAAD. METHODS: TAAAD patients (N = 2,765) enrolled in the International Registry of Acute Aortic Dissection were stratified based on normal (n = 1,094 [39.6%]) and abnormal (n = 1,671 [60.4%]) findings on presenting ECGs and further subdivided according to specific ECG findings. Time data are presented in hours as medians (quartile 1 to quartile 3). RESULTS: Patients with ECGs with abnormal findings presented to the hospital sooner after symptom onset than those with ECGs with normal findings (1.4 [0.8 to 3.3] vs 2.0 [1.0 to 3.3]; p = 0.005). Specifically, this was seen in patients with infarction with new Q waves or ST elevation (1.3 [0.6 to 2.7] vs 1.5 [0.8 to 3.3]; p = 0.049). Interestingly, the time between symptom onset and diagnosis was longer with infarction with old Q waves (6.7 [3.2 to 18.4] vs 5.0 [2.9 to 11.8]; p = 0.034) and nonspecific ST-T changes (5.8 [3.0 to 13.8] vs 4.5 [2.8 to 10.5]; p = 0.002). Surgical mortality was higher in patients with abnormal ECG findings (20.6% vs 11.9%, p < 0.001), especially in those with ischemia by ECG (25.7% vs 16.8%, p < 0.001) and infarction with new Q waves or ST elevation (30.1% vs 17.1%, p < 0.001). CONCLUSIONS: TAAAD patients presenting with abnormal ECG results are sicker, have more in-hospital complications, and are more likely to die. The frequency of nonspecific ST-T abnormalities and its association with delay in diagnosis and treatment presents an opportunity for practice improvement.

Chronobiology of Acute Aortic Dissection in the Marfan Syndrome (from the National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions and the International Registry of Acute Aortic Dissection).

Marfan syndrome (MFS) is an autosomal dominant connective tissue disease associated with acute aortic dissection (AAD). We used 2 large registries that include patients with MFS to investigate possible trends in the chronobiology of AAD in MFS. We queried the International Registry of Acute Aortic Dissection (IRAD) and the Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) registry to extract data on all patients with MFS who had suffered an AAD. The group included 257 patients with MFS who suffered an AAD from 1980 to 2012. The chi-square tests were used for statistical testing. Mean subject age at time of AAD was 38 years, and 61% of subjects were men. AAD was more likely in the winter/spring season (November to April) than the other half of the year (57% vs 43%, p = 0.05). Dissections were significantly more likely to occur during the daytime hours, with 65% of dissections occurring from 6 a.m. to 6 p.m. (p = 0.001). Men were more likely to dissect during the daytime hours (6 a.m. to 6 p.m.) than women (74% vs 51%, p = 0.01). These insights offer a glimpse of the times of greatest vulnerability for patients with MFS who suffer from this catastrophic event. In conclusion, the chronobiology of AAD in MFS reflects that of AAD in the general population.

IRAD experience on surgical type A acute dissection patients: results and predictors of mortality.

Type A acute aortic dissection (TAAD) is a disease that has a catastrophic impact on a patient's life and emergent surgery represents a key goal of early treatment. Despite continuous improvements in imaging techniques, medical therapy and surgical management, early mortality in patients undergoing TAAD repair still remains high, ranging from 17% to 26%. In this setting, the International Registry of Acute Aortic Dissection (IRAD), the largest worldwide registry for acute aortic dissection, was established to assess clinical characteristics, management and outcomes of TAAD patients. The present review aimed to evaluate and comment on outcomes of TAAD surgery as reported from IRAD series.

Predicting in-hospital mortality in acute type B aortic dissection: evidence from International Registry of Acute Aortic Dissection.

BACKGROUND: The outcome of patients with acute type B aortic dissection (ABAD) is strongly related to their clinical presentation. The purpose of this study was to investigate predictors for mortality among patients presenting with ABAD and to create a predictive model to estimate individual risk of in-hospital mortality using the International Registry of Acute Aortic Dissection (IRAD). METHODS AND RESULTS: All patients with ABAD enrolled in IRAD between 1996 and 2013 were included for analysis. Multivariable logistic regression analysis was used to investigate predictors of in-hospital mortality. Significant risk factors for in-hospital death were used to develop a prediction model. A total of 1034 patients with ABAD were included for analysis (673 men; mean age, 63.5±14.0 years), with an overall in-hospital mortality of 10.6%. In multivariable analysis, the following variables at admission were independently associated with increased in-hospital mortality: increasing age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.00-1.06; P=0.044), hypotension/shock (OR, 6.43; 95% CI, 2.88-18.98; P=0.001), periaortic hematoma (OR, 3.06; 95% CI, 1.38-6.78; P=0.006), descending diameter ≥5.5 cm (OR, 6.04; 95% CI, 2.87-12.73; P<0.001), mesenteric ischemia (OR, 9.03; 95% CI, 3.49-23.38; P<0.001), acute renal failure (OR, 3.61; 95% CI, 1.68-7.75; P=0.001), and limb ischemia (OR, 3.02; 95% CI, 1.05-8.68; P=0.040). Based on these multivariable results, a reliable and simple bedside risk prediction tool was developed. CONCLUSIONS: We present a simple prediction model using variables that are independently associated with in-hospital mortality in patients with ABAD. Although it needs to be validated in an independent population, this model could be used to assist physicians in their choice of management and for informing patients and their families.

Cardiac implantable electronic device reutilization: battery life of explanted devices at a tertiary care center.

INTRODUCTION: Prior studies have suggested that pacemaker reuse may be a reasonable alternative to provide device therapy in the low- and middle-income countries. We studied explant indications and remaining battery life of cardiac implantable electronic devices (CIEDs) at a tertiary medical center. METHODS AND RESULTS: We conducted a retrospective review of all CIEDs extracted at the University of Michigan between 2007 and 2011. Devices were considered reusable if battery longevity was ≥48 months or >75% battery life was remaining; there was no evidence of electrical malfunction, and they were not under advisory or recall. Eight hundred and one CIEDs were explanted: Medtronic (MDT [Medtronic Inc., Minneapolis, MN, USA]; 454), Boston Scientific (BS [Boston Scientific Corp., Natick, MA, USA])/Guidant (GDT; 255 [Guidant Corp., St. Paul, MN, USA]), St. Jude Medical (SJM; 73 [St. Paul, MN, USA]), and Biotronik (BTK; 15 [Biotronik GmBH, Berlin, Germany]). After eliminating devices explanted for elective replacement indicator (ERI, 541), 51.9% of pacemakers (41/79), 54.2% of implantable cardioverter-defibrillators (ICDs) (64/118), and 47.6% of cardiac resynchronization therapy and defibrillation (CRT-D) devices (30/63) had sufficient battery life and no evidence of electrical malfunction to be considered for reuse. A logistic regression analysis found that the indications for device removal independently predicted reusability: upgrade to an ICD (odds ratio [OR] 162.8, P < 0.001) or CRT-D (OR 63.8, P < 0.001), infection (OR 110.7, P < 0.001), heart transplantation or left ventricular assist device placement (OR 56.6, P < 0.001), and device removal at patient's request (OR 115.4, P < 0.001). CONCLUSION: The majority of explanted CIEDs for reasons other than ERI have an adequate battery life and, if proven safe, may conceivably be reutilized for basic pacing in underserved nations where access to this life-saving therapy is limited.

Painless Type B Aortic Dissection: Insights From the International Registry of Acute Aortic Dissection.

INTRODUCTION: The classical presentation of a patient with Type B acute aortic dissection (TBAAD) is characterized by severe chest, back, or abdominal pain, ripping or tearing in nature. However, some patients present with painless acute aortic dissection, which can lead to a delay in diagnosis and treatment. We utilized the International Registry on Acute Aortic Dissections (IRAD) database to study these patients. METHODS: We analyzed 43 painless TBAAD patients enrolled in the database between January 1996 and July 2012. The differences in presentation, diagnostics, management, and outcome were compared with patients presenting with painful TBAAD. RESULTS: Among the 1162 TBAAD patients enrolled in IRAD, 43 patients presented with painless TBAAD (3.7%). The mean age of patients with painless TBAAD was significantly higher than normal TBAAD patients (69.2 versus 63.3 years, P = 0.020). The presence of atherosclerosis (46.4% versus 30.1%, P = 0.022), diabetes (17.9% versus 7.5%; P = 0.018), and other aortic diseases (8.6% versus 2.3%, P= 0.051), such as prior aortic aneurysm (31% versus 18.8% P = 0.049) was more common in these patients. Median delay time between presentation and diagnosis was longer in painless patients (median 34.0 versus 19.0 hours; P = 0.006). Dissection of iatrogenic origin (19.5% versus 1.3%; P < 0.001) was significantly more frequent in the painless group. The in-hospital mortality was 18.6% in the painless group, compared with an in-hospital mortality of 9.9% in the control group (P = 0.063). CONCLUSION: Painless TBAAD is a relatively rare presentation (3.7%) of aortic dissection, and is often associated with a history of atherosclerosis, diabetes, prior aortic disease including aortic aneurysm, and an iatrogenic origin. We observed a trend for increased in-hospital mortality in painless TBAAD patients, which may be the result of a delay in diagnosis and management. Therefore, physicians should be aware of this relative rare presentation of TBAAD.

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.