Strain Analysis in Patients with Frequent Premature Ventricular Complexes and Preserved Left Ventricular Function Undergoing Ablation.

BACKGROUND: Frequent premature ventricular complexes (PVCs) can cause PVC-induced cardiomyopathy. The value of PVC ablation in patients with preserved left ventricular function in the low-normal range (ejection fraction: 50-55%) is not established. Strain analysis has been used to estimate changes in left ventricular function beyond assessment of the ejection fraction (EF). Longitudinal strain has been proposed as a method to detect changes over time in the setting of frequent asymptomatic premature ventricular complexes and preserved left ventricular (LV) function. A decrease in strain may be evidence of PVC-induced cardiomyopathy. OBJECTIVE: In this study, we assessed the role of PVC ablation in patients with low-normal EF and the effect on EF and myocardial strain before and after PVC ablation. METHODS: A total of 70 consecutive patients with either low-normal EF (0.5-<0.55, n = 35) or high-normal EF (≥0.55; n = 35), using available imaging and Holter data, were referred for ablation due to frequent PVCs. EF and longitudinal strain were assessed pre- and post-ablation. RESULTS: There was a significant increase in EF (53.2 ± 0.4% to 58.3 ± 0.5%, p < 0.001) and improvement in longitudinal strain (-15.2 ± 3.3 to -16.6 ± 3, p = 0.007) post-ablation in patients with low-normal EF and successful ablation. There was no change in EF or longitudinal strain in patients with high-normal EF and a successful ablation pre- vs. post-ablation. CONCLUSIONS: Patients with frequent PVCs and low-normal LV EF compared to patients with frequent PVCs and high-normal LV EF have evidence of PVC-induced cardiomyopathy and may benefit from ablation despite a preserved left ventricular EF.

Spontaneous Coronary Artery Dissection: An Underdiagnosed Clinical Entity-A Primer for Cardiac Imagers.

Spontaneous coronary artery dissection (SCAD) is a nonatherosclerotic cause of myocardial infarction in young and middle-aged women that has gained increasing awareness in recent years. Its diagnosis presents a challenge. Invasive coronary angiography is the primary imaging modality for diagnosing SCAD; however, it carries risk in these patients, who have an increased predisposition to complications. Advances in CT technology enable robust noninvasive evaluation of the coronary arteries at low radiation doses and have been increasingly utilized for the diagnosis or resolution of SCAD, in hemodynamically stable patients or when diagnosis of SCAD is uncertain at invasive angiography, particularly in proximal vessels. However, criteria for the diagnosis of SCAD with use of coronary CT angiography (CCTA) have not been currently established, and sensitivity and specificity for diagnosis have not yet been defined. The appearance of SCAD at CCTA can be subtle and can be missed, especially in distal small-caliber coronary arteries; hence utilization of other noninvasive imaging multimodalities may help solve this diagnostic challenge. Accurate and prompt diagnosis is vital, as management of SCAD differs significantly from that of traditional atherosclerotic acute coronary syndromes, with conservative management preferred for the majority of SCAD patients, and invasive treatment reserved for those with ongoing or recurrent ischemia, heart failure, or hemodynamic compromise. The goal of this review is twofold: (a) to discuss the potential role of CCTA in the diagnosis of SCAD, and (b) to discuss the role of multimodality imaging that may improve diagnostic yield, guide management, and enable subsequent surveillance. An invited commentary by Ordovas is available online. Online supplemental material is available for this article. ©RSNA, 2021.

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.

Effect of Race on Echocardiographic Measures of Cardiac Structure and Function.

The relations between race and cardiac structure and function are incompletely understood. We hypothesized that race-specific differences in echocardiography measurements exist. We compared the relation between echocardiography measurements and race among 12,429 nonobese adults without known cardiovascular disease who underwent echocardiography. We compared measurements between whites (n = 10,508), blacks (n = 792), Asians (n = 628), Hispanics (n = 315), Native Americans (n = 34), and multiracial/other (n = 152) cohorts. Multivariate analysis compared measurements indexed to body surface area (BSA) between races and adjusted for variables including age, gender, and mean blood pressure. Mean age was 46.9 ± 17.4 years and 60.5% were women. After multivariable adjustment and using whites as a baseline, there were significant differences (p <0.05) in left ventricular end-diastolic diameter/BSA for blacks (-0.5 mm/m2), Asians (0.4 mm/m2), Hispanics (0.2 mm/m2), and multiracial/others (0.1 mm/m2); septal wall thickness/BSA for blacks (0.4 mm/m2) and Asians (0.1 mm/m2); posterior wall thickness/BSA for blacks (0.4 mm/m2), Asians (0.1 mm/m2), Hispanics (0.04 mm/m2), and multiracial/others (0.03 mm/m2); left atrial diameter/BSA for Asians (0.2 mm/m2), Hispanics (0.3 mm/m2), and multiracial/others (0.1 mm/m2); septal and lateral e' for blacks (-0.7 cm/s; -0.9 cm/s); and peak tricuspid regurgitation gradient for blacks (4.3 mm Hg) and Asians (-0.9 mm Hg). Race is associated with significant differences in left ventricular size, left atrial size, mitral annular velocity, and tricuspid regurgitation gradient. Normal reference ranges for echocardiography measurements should utilize racially diverse cohorts to prevent misclassification of echocardiography findings based on race.

Differences in Echocardiographic Measures of Aortic Dimensions by Race.

It is not clear whether there are differences in aortic dimensions by race. Our hypothesis was that race-specific differences in aortic size exist. We compared the relation between race and aortic dimensions among 15,295 adults without known risk factors for cardiovascular disease or aortic dilatation, who underwent clinically indicated transthoracic echocardiography. We compared inner edge-to-inner edge measurements between whites (n = 12,932), blacks (n = 958), Asians (n = 827), Hispanics (n = 366), Native Americans (n = 38), and others (n = 174). Multivariate analysis compared measurements indexed with body surface area (BSA) between races and adjusted for variables including age, gender, and mean blood pressure. Mean age was 49.9 ± 17.6 years, and 58.7% were female. On gender-specific comparisons, there were significant differences in aortic size between races (p <0.001 for each). Using whites as a baseline, multivariable analysis demonstrated that blacks had smaller BSA-indexed aortic sinus (-0.34 mm/m2, p <0.001) and ascending aorta (-0.43 mm/m2, p <0.001) dimensions; Asians had larger BSA-indexed aortic sinus (0.36 mm/m2, p <0.001), ascending aorta (0.41 mm/m2, p <0.001), and aortic arch (0.20 mm/m2, p = 0.002) dimensions; Hispanics had larger BSA-indexed aortic arch dimensions (0.15 mm/m2, p = 0.01); Native Americans had increased BSA-indexed aortic arch dimensions (0.32 mm/m2, p = 0.01); and other races had increased BSA-indexed aortic arch dimensions (0.11 mm/m2, p = 0.03). In a cohort without known risk factors for aortic dilatation, race is associated with significant differences in aortic dimensions. In conclusion, these findings suggest that reference ranges for aortic size should be established using racially diverse cohorts to prevent misdiagnosis of aortic dilatation based on race.

Indexing left ventricular wall thickness to body surface area improves prognostic value.

BACKGROUND: Guidelines provide normal ranges of left ventricular (LV) wall thicknesses (WT) without indexing. We hypothesized that indexing WT to body surface area (BSA) improves prognostic value. METHODS: We examined the relationship between WT and BSA in 9737 patients undergoing echocardiography without risk factors for LV hypertrophy other than obesity. We compared WT to BSA and examined the relationship of WT and LV mass index (LVMI) to mortality. RESULTS: There is a linear relationship between BSA and septal and posterior WT (r = 0.38, P < 0.001 for each). Higher quartiles of BSA were associated with increased WT (P < 0.001). After adjusting for age and gender, greater mean WT (MWT) (Hazards Ratio [HR] 1.10 per mm, 95% Confidence Interval [CI] 1.04-1.16, P = 0.001, C-statistic 0.66), LVMI (HR 1.01, 95% CI 1.001-1.01, P = 0.01, C-statistic 0.66), and indexed MWT (HR 1.34 per mm/m2 , 95% CI 1.23-1.47, P < 0.001, C-statistic 0.67) are each associated with increased mortality, with indexed MWT having the highest prognostic value. Each decile of indexed MWT ≥8th decile was associated with increased mortality compared to the 1st decile (P < 0.01 for each). Individuals with indexed MWT ≥8th decile (≥5.0 mm/m2 ) had increased adjusted mortality (HR 1.67, 95% CI 1.43-1.94, P < 0.001, C-statistic 0.67); this had improved prognostic value over guideline definitions of increased MWT (C-statistic 0.66) or LVMI (P = NS). CONCLUSIONS: We observe a linear relationship between BSA and WT. Indexing WT improves mortality prediction over LVMI and nonindexed WT. These findings support indexing WT to BSA.

Extracorporeal Membrane Oxygenation in a 29-Year-Old Man with Pneumocystis jirovecii Respiratory Failure and AIDS.

The use of extracorporeal membrane oxygenation (ECMO) in patients who have acute respiratory distress syndrome has been generally beneficial. However, because of various concerns, ECMO has rarely been used in patients who have human immunodeficiency virus infection with or without acquired immune deficiency syndrome. We report our successful use of venovenous ECMO in a 29-year-old man who presented with severe respiratory distress secondary to Pneumocystis jirovecii pneumonia associated with undiagnosed infection with the human immunodeficiency virus and acquired immune deficiency syndrome. After highly active antiretroviral therapy was begun, acute immune reconstitution inflammatory syndrome developed. The patient's respiratory condition deteriorated rapidly; he was placed on venovenous ECMO for 19 days and remained intubated thereafter. After a 65-day hospital stay and inpatient pulmonary rehabilitation, he recovered fully. In addition to presenting this case, we review the few previous reports and note the multidisciplinary medical and surgical support necessary to treat similar patients.

Presenting Systolic Blood Pressure and Outcomes in Patients With Acute Aortic Dissection.

BACKGROUND: Presenting systolic blood pressure (SBP) is a powerful predictor of mortality in many cardiovascular settings, including acute coronary syndromes, cardiogenic shock, and acute heart failure. OBJECTIVES: This study evaluated the association of presenting SBP with in-hospital outcomes, specifically all-cause mortality, in acute aortic dissection (AAD). METHODS: The study included 6,238 consecutive patients (4,167 with type A and 2,071 with type B AAD) enrolled in the International Registry of Acute Aortic Dissection. Patients were stratified in 4 groups according to presenting SBP: SBP >150, SBP 101 to 150, SBP 81 to 100, or SBP ≤80 mm Hg. RESULTS: The relationship between presenting SBP and in-hospital mortality displayed a J-curve association, with significantly higher mortality rates in patients with very high SBP (26.3% for SBP >180 mm Hg in type A AAD, 13.3% for SBP >200 mm Hg in type B AAD; p = 0.005 and p = 0.018, respectively) as well as in those with SBP ≤100 mm Hg (29.9% in type A, 22.4% in type B; p = 0.033 and p = 0.015, respectively). This relationship was mainly from increased rates of in-hospital complications (acute renal failure, coma, and mesenteric ischemia/infarction in patients with SBP >150 mm Hg; stroke, coma, cardiac tamponade, myocardial ischemia/infarction, and acute renal failure in patients with SBP ≤80 mm Hg). Notably, presenting SBP ≤80 mm Hg was independently associated with in-hospital mortality in both type A (p = 0.001) and type B AAD (p = 0.003). CONCLUSIONS: Presenting SBP showed a clear J-curve relationship with in-hospital mortality in patients with AAD. Although this association was related to increased rates of comorbid conditions at the edges of the curve, SBP ≤80 mm Hg was an independent correlate of in-hospital mortality.

Acute aortic syndromes: diagnosis and management, an update.

Acute aortic syndromes (AAS) encompass a constellation of life-threatening medical conditions including classic acute aortic dissection (AAD), intramural haematoma, and penetrating atherosclerotic aortic ulcer. Given the non-specific symptoms and physical signs, a high clinical index of suspicion is necessary to detect the disease before irreversible lethal complications occur. In order to reduce the diagnostic time delay, a comprehensive flowchart for decision-making based on pre-test sensitivity of AAS has been designed by the European Society of Cardiology guidelines on aortic diseases and should be thus applied in the emergency scenario. When the definitive diagnosis is made, prompt and appropriate therapeutic interventions should be undertaken if indicated by a highly specialized aortic team. Urgent surgery for AAD involving the ascending aorta (Type A) and medical therapy alone for AAD not involving the ascending aorta (Type B) are typically recommended. In complicated Type B AAD, thoracic endovascular aortic repair (TEVAR) is generally indicated. On the other hand, in uncomplicated Type B AAD, pre-emptive TEVAR rather than medical therapy alone to prevent late complications, while intuitive, requires further study in randomized cohorts. Finally, it should be highlighted that there is an urgent need to increase awareness of AAS worldwide, including dedicated education/prevention programmes, and to improve diagnostic and therapeutic strategies, outcomes, and lifelong surveillance.

Anomalous Coronary Arteries That Need Intervention: Review of Pre- and Postoperative Imaging Appearances.

Coronary artery anomalies constitute a diverse group of abnormalities, ranging from anatomic variants to those having hemodynamic consequences. This review focuses on major anomalies that have clinical implications requiring treatment, including anomalous origin of the coronary artery from the opposite sinus with interarterial course specifically with an intramural course, coronary artery origin from the pulmonary artery, and coronary artery fistula. Comprehensive imaging evaluation is necessary to precisely delineate the anatomy as well as pathophysiologic aspects of the anomaly before determining treatment options for a specific patient. Coronary computed tomographic angiography provides elegant depiction of coronary arterial anatomy and the relationship of the vessel to the adjacent structures, with the ability to perform three-dimensional reconstructions. Magnetic resonance (MR) imaging is emerging as an alternative noninvasive imaging strategy, particularly in young individuals, due to the lack of ionizing radiation and avoidance of iodinated contrast agents. This review describes the roles and recent technical advancements in computed tomography and MR imaging pertinent to coronary artery imaging. Additionally, this article will familiarize readers with the cross-sectional imaging appearance of clinically relevant coronary anomalies, hemodynamic considerations, and complex decision making. The different management strategies used for these anomalies, such as coronary unroofing, reimplantation, bypass grafting, Takeuchi repair, and surgical and interventional closure of fistulas, as well as specific posttreatment complications, are also discussed. ©RSNA, 2017.

Utilization of "Stand-By" Extracorporeal Membrane Oxygenation in a High-Risk Parturient With Methamphetamine-Associated Cardiomyopathy Undergoing Dilation and Evacuation: A Case Report.

Parturients may present with evidence of acute heart failure or respiratory distress during the peripartum period. This case report documents utilization of "stand-by" extracorporeal membrane oxygenation (ECMO) for a 40-year-old woman with a history of severe left ventricular dysfunction who presented for elective dilation and evacuation of triplets at 20 weeks' gestation. The patient's medical history was significant for hypertension, diabetes mellitus, methamphetamine use (acute/chronic), and cardiac-respiratory arrest before her previous emergent cesarean delivery. The patient underwent general anesthesia with the placement of peripheral venous and arterial cannulas for "stand-by" ECMO. The patient remained stable throughout the procedure, and "stand-by" ECMO was not initiated; the patient was discharged 5 days' postprocedure. The use of "stand-by" ECMO in the parturient with severe cardiopulmonary dysfunction is still in its infancy. Centers managing populations of both high-risk parturients and nonparturients may consider development of algorithms for implementation and utilization of ECMO.

SYNTAX Score Derived From Coronary CT Angiography for Prediction of Complex Percutaneous Coronary Interventions.

RATIONALE AND OBJECTIVES: SYNTAX score is a useful metric determined at the time of invasive coronary angiography (ICA) to assess the complexity of coronary artery disease, and improves prediction of complications at the time of percutaneous complex intervention (PCI). We aimed to determine whether SYNTAX score can be reliably determined from coronary computed tomography angiography (CCTA) and whether a CCTA-derived SYNTAX score can predict complex PCI. MATERIALS AND METHODS: SYNTAX scores were calculated on per-patient, per-vessel, and per-segment basis in 154 consecutive patients who underwent CCTA and ICA. PCI complexity in 113 patients who underwent intervention was defined by total fluoroscopy time and contrast volume. RESULTS: Compared to ICA, CCTA detected 285 of 302 (94%) obstructive lesions in 230 vessels, for which PCI was performed for 154 lesions in 131 vessels. Overall, on a per-patient basis, ICA-derived SYNTAX score was lower in comparison to CCTA-derived score (10.2 ± 8.0 vs 10.9 ± 8.3, P = 0.001). As compared to lesions in the lowest CCTA-derived segmental SYNTAX tertile, lesions in the highest tertile required longer fluoroscopy time (17.5 ± 12 min vs 11.5 ± 7.9 min, P = 0.01) and greater contrast volume (215.4 ± 125.5 mL vs 144.3 ± 49 mL, P = 0.02). CONCLUSION: SYNTAX scores derived from CCTA are concordant with those derived from ICA and correspond with complex PCI.

Iterative Reconstruction Results in Larger Computed Tomography Measurements of Iliofemoral Artery Diameter in Patients Referred for Transcatheter Aortic Valve Replacement.

OBJECTIVES: We hypothesized that improved iterative reconstruction increases image quality and reduces artifacts for iliofemoral artery computed tomography imaging in patients referred for transcatheter aortic valve replacement (TAVR). METHODS: We examined 56 consecutive patients undergoing computed tomography for possible TAVR and compared image quality and iliofemoral artery size between adaptive statistical iterative reconstructions (ASIRs) and improved model-based iterative reconstructions (MBIRs). RESULTS: Model-based iterative reconstruction (vs ASIR) was associated with improved (P < 0.001 for each) image quality (3.4 ± 0.8 vs 2.8 ± 1.0), beam hardening (3.5 ± 0.8 vs 3.0 ± 1.1), and wall definition (3.6 ± 0.6 vs 3.1 ± 0.8). Image signal-to-noise ratios (20.4 ± 10.1 vs 13.7 ± 6.6, P < 0.001) were also increased with MBIR as compared with ASIR. Mean iliofemoral artery size was larger using MBIR compared with ASIR (left, 7.7 ± 1.5 vs 7.4 ± 1.7 mm, P < 0.001; right, 7.8 ± 1.2 vs 7.4 ± 1.5 mm, P = 0.008). CONCLUSIONS: In patients referred for TAVR, improved MBIR resulted in higher image quality, reduced artifacts, and larger iliofemoral artery diameters compared with standard iterative reconstructions.

Effect of circadian variability in frequency of premature ventricular complexes on left ventricular function.

BACKGROUND: Frequent idiopathic premature ventricular complexes (PVCs) can result in a reversible form of cardiomyopathy. OBJECTIVE: The purpose of this study was to assess the impact of variability in PVC frequency throughout the day on PVC-induced cardiomyopathy. METHODS: The subjects of this study were 107 consecutive patients (58 men [54%]; mean age 49.7 ± 15.0 years; left ventricular ejection fraction 50.4% ± 11.4%) referred for ablation of frequent PVCs. All patients underwent 24-hour Holter monitoring before the ablation procedure. The circadian variation in PVC burden was determined and correlated with the presence or absence of cardiomyopathy. RESULTS: A total of 43 patients (40%) had cardiomyopathy. Patients with cardiomyopathy had an ejection fraction of 38.4% ± 6.9%, a higher PVC burden (28.5% ± 11.5% vs 19.5% ± 10.5%; P = .0001), less variability in circadian PVC distribution (coefficient of variation hourly: 31.5% ± 21% vs 59.8% ± 32.4%; P = .0001), and more frequent interpolated PVCs (20 patients [47%] vs 15 patients [23%]; P = 0.022), and were more frequently asymptomatic than patients without cardiomyopathy (56% vs 19%; P = .0001). In multivariate analysis, consistency in PVC burden throughout the day was an independent predictor of PVC-induced cardiomyopathy (odds ratio 16.3; 95% confidence interval 1.7-155.3; p = 0.015). CONCLUSION: In patients with frequent PVCs, consistency in hourly PVC frequency throughout the day is an independent predictor of PVC-induced cardiomyopathy.