Cynthia C. Taub

Cardiac imaging for assessment of left atrial appendage stasis and thrombosis

Atrial fibrillation (AF) is the most-common arrhythmia in the elderly population (age >65 years). The left atrial appendage (LAA) is the main location of thrombus formation, predominantly in patients with nonvalvular AF. This Review is focused on the pathophysiology, assessment, and clinical implications of stasis (or spontaneous echocardiographic contrast; SEC) and thrombus formation in the LAA. The gold-standard modality for assessment of SEC and thrombus in the LAA is echocardiography, particularly transoesophageal echocardiography (TEE). Cardiac CT (CCT) is an accurate, noninvasive alternative to TEE for the detection of LAA thrombi, distinctly when delayed-imaging acquisition protocols are used. Prospective studies to validate the use of cardiac MRI (CMR) for this purpose are needed, and will avoid the need for radiation and iodinated contrast. CCT or CMR could potentially be implemented to rule out LAA thrombus, avoiding unnecessary preprocedural TEE. Cardiac imaging is also of primary importance in the setting of LAA closure devices and electrophysiological studies. New trials are needed to compare the various imaging modalities, with surgicopathological findings as a reference standard.

A meta-analysis and meta-regression of long-term outcomes of transcatheter versus surgical aortic valve replacement for severe aortic stenosis

BACKGROUND Transcatheter aortic valve replacement (TAVR) has emerged as an alternative to surgical aortic-valve replacement (SAVR) for patients with severe symptomatic aortic stenosis (AS) who are at high operative risk. We sought to determine the long-term (≥1year follow-up) safety and efficacy TAVR compared with SAVR in patients with severe AS. METHODS A comprehensive search of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, conference proceedings, and relevant Web sites from inception through 10 April 2016. RESULTS Fifty studies enrolling 44,247 patients met the inclusion criteria. The mean duration follow-up was 21.4months. No difference was found in long-term all-cause mortality (risk ratios (RR), 1.06; 95% confidence interval (CI) 0.91-1.22). There was a significant difference favoring TAVR in the incidence of stroke (RR, 0.82; 95% CI 0.71-0.94), atrial fibrillation (RR, 0.43; 95% CI 0.33-0.54), acute kidney injury (RR, 0.70; 95% CI 0.53-0.92), and major bleeding (RR, 0.57; 95% CI 0.40-0.81). TAVR had significant higher incidence of vascular complications (RR, 2.90; 95% CI 1.87-4.49), aortic regurgitation (RR, 7.00; 95% CI 5.27-9.30), and pacemaker implantation (PPM) (RR, 2.02; 95% CI 1.51-2.68). TAVR demonstrated significantly lower stroke risk compared to SAVR in high-risk patients (RR, 1.49; 95% CI 1.06-2.10); no differences in PPM implantation were observed in intermediate-risk patients (RR, 1.68; 95% CI 0.94-3.00). In a meta-regression analysis, the effect of TAVR baseline clinical features did not affect the long-term all-cause mortality outcome. CONCLUSION TAVR and SAVR showed similar long-term survival in patients with severe AS; with important differences in treatment-associated morbidity.

Sapien 3 versus Sapien XT prosthetic valves in transcatheter aortic valve implantation: A meta-analysis

OBJECTIVES The S3 prosthetic valve was introduced to overcome several issues with its predecessor, the SXT, in transcatheter aortic valve implantation (TAVI), however, the clinical outcomes of this new model are not clearly defined. We performed a meta-analysis to compare the outcomes in Sapien 3 (S3) and Sapien XT (SXT) recipients. METHODS A literature search through PUBMED and EMBASE was conducted. Articles that included at least one of the clinical outcomes of interest were included in the meta-analysis: moderate to severe paravalvular regurgitation (PVR), permanent pacemaker implantation (PPI), major vascular complications (MVC), cerebrovascular events (stroke and transient ischemic attack) (CVE), failure rate of device implantation, life-threatening, disabling or major bleeding, need for post-dilation and early all-cause-mortality. RESULTS A total of 9 observational cohort studies were included. S3 was implanted in 945 and SXT in 1553 patients. S3 was associated with a lower incidence of moderate to severe PVR (1.6% vs 6.9%, p<0.0001), lower MVC (5.1% vs 8.9%, p=0.01) and less serious bleeding (8.1% vs 15.2%, p=0.003) compared to the SXT. Device deployment failure rate was lower in the S3 (1.2% vs 5.9%, p=0.004) and the S3 required less post-dilation (16.9% vs 26.9%, p=0.05). Rates of CVE, perioperative mortality and PPI were similar between the two valves. CONCLUSIONS Implantation of the S3 prosthetic valve results in lower rates of moderate to severe PVR, MVC, post-dilation and serious bleeding however it does not improve on the SXT in terms of CVE, PPI and early mortality.

Racial Disparities in Cardiac Rehabilitation Initiation and the Effect on Survival

To examine predictors of initiation and adherence, identify racial disparities, and compare the survival benefit of cardiac rehabilitation between a white and a unique predominantly non‐white minority in an urban environment.

Methadone, QTc prolongation and torsades de pointes: Current concepts, management and a hidden twist in the tale?

Methadone is a drug that has found widespread utility in the management of opioid addiction and pain. Along with its popularity, methadone has also earned an infamous reputation for causing prolongation of the QT interval and an increased risk of torsades de pointes. In this article we will give a brief overview of the long QT syndromes, followed by an in-depth look at the current pathophysiologic mechanisms of methadone induced QT prolongation, a review of the existing literature and the current concepts regarding the prevention and management of methadone induced torsades de pointes. In addition, we explore the idea and implications of a genetic link between methadone induced prolongation of the QT interval and torsades de pointes.

Non-invasive assessment of low risk acute chest pain in the emergency department: A comparative meta-analysis of prospective studies

BACKGROUND The aim of this meta-analysis was to compare the diagnostic accuracy of cardiac computed tomographic angiography (CCTA), stress echocardiography (SE) and radionuclide single photon emission computed tomography (SPECT) for the assessment of chest pain in emergency department (ED) setting. METHODS A systematic review of Medline, Cochrane and Embase was undertaken for prospective clinical studies assessing the diagnostic efficacy of CCTA, SE or SPECT, as compared to intracoronary angiography (ICA) or the later presence of major adverse clinical outcomes (MACE), in patients presenting to the ED with chest pain. Standard approach and bivariate analysis were performed. RESULTS Thirty-seven studies (15 CCTA, 9 SE, 13 SPECT) comprising a total of 7800 patients fulfilled inclusion criteria. The respective weighted mean sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and total diagnostic accuracy for CCTA were: 95%, 99%, 84%, 100% and 99%, for SE were: 84%, 94%, 73%, 96% and 96%, and for SPECT were: 85%, 86%, 57%, 95% and 88%. There was no significant difference between modalities in terms of NPV. Bivariate analysis revealed that CCTA had statistically greater sensitivity, specificity, PPV and overall diagnostic accuracy when compared to SE and SPECT. CONCLUSIONS All three modalities, when employed by an experienced clinician, are highly accurate. Each has its own strengths and limitations making each well suited for different patient groups. CCTA has higher accuracy than SE and SPECT, but it has many drawbacks, most importantly its lack of physiologic data.

Iatrogenic Ventricular Septal Defect Following Transcatheter Aortic Valve Replacement: A Systematic Review.

BACKGROUND Ventricular septal defects (VSD) are rarely reported as a complication following transcatheter aortic valve replacement (TAVR). We sought to characterise the patients, clinical management, and outcomes regarding this rare phenomenon. METHODS Relevant articles were identified by a systematic search of MEDLINE and EMBASE databases from January, 2002 to September, 2015. RESULTS A total of 18 case reports, including 20 patients, were identified. The median age was 83 years and six were male. Twelve were performed by trans-femoral approach. Pre-dilation was performed in 12 patients and post-dilation in four. Balloon expandable valves were used in the majority (85%) of cases. The clinical presentation varied from asymptomatic to progressive heart failure. The timing of the diagnosis also varied significantly from immediately post valve implantation to one year afterwards. There were two cases of Gerbode-type defect while the rest were inter-ventricular defects. The location was mostly membranous or perimembranous (79%) and adjacent to the valve landing zone. A total of seven interventions (one open surgery and six percutaneous closure) were performed. Four patients died during the same hospital admission. Sixteen survived past discharge (range 12 days to two years). CONCLUSIONS Ventricular septal defects post-TAVR were seen more with balloon expandable valves and with pre-dilation or post-dilation. Percutaneous treatment of the VSD was preferred over open cardiac surgery given the high surgical risk in this patient population. Some, but not all, patients survived TAVR and VSD and had a good prognosis for both patient groups with or without VSD closure.

Novel Imaging Approaches for Predicting Arrhythmic Risk.

Determination of ventricular arrhythmic risk is crucial for guiding management of cardiac disease. Although for patients at increased risk an implantable cardioverter-defibrillator is recommended, it is widely acknowledged that current criteria for device use based predominantly on left ventricular ejection fraction are deficient. Genesis of ventricular arrhythmias involves a complex interaction of myocardial substrate abnormalities, precipitating triggers, and modulating factors. There are much data showing that by more directly assessing these factors, noninvasive imaging using echocardiography, radionuclide imaging, and cardiac magnetic resonance enhances arrhythmic risk stratification beyond ejection fraction and commonly used electrocardiographic and serum biomarkers. It is anticipated that further technological advancements studied in well-designed clinical trials will provide both more precise determination of risk and guide therapies to enhanced survival and patient well-being.

Continuous Apex to Left Ventricle Blood Flow Pattern in Hypertrophic Cardiomyopathy with Apical Aneurysm and Midventricular Obstruction

A 42‐year‐old female presented with chest pain, noted to have systolic and diastolic murmurs on physical examination and left ventricular hypertrophy on the electrocardiogram. Echocardiography with contrast enhancement revealed hypertrophic cardiomyopathy (HCM) with apical aneurysm and mid left ventricular cavity obstruction. Doppler interrogation showed continuous systolic and diastolic flow from the apex to left ventricle (LV) with a transient deceleration giving rise to a notched pattern. Myocardial ischemia of the apex was demonstrated on adenosine nuclear scintigraphy without epicardial coronary obstruction on angiography. This case demonstrates a novel Doppler pattern with continuous apex to LV flow in HCM in the setting of apical ischemia that may account for the formation of the aneurysm. (Echocardiography 2012;29:E131‐E133)

Spontaneous coronary artery dissection causing acute myocardial infarction in a 62-year-old postmenopausal woman without co-morbidities: a case report

IntroductionSpontaneous coronary artery dissection is an important yet rare cause of acute coronary syndrome. The available literature shows a higher risk factor for women, notably during pregnancy and puerperium. The incidence in postmenopausal women is exceedingly rare, and is more commonly seen in association with concurrent predisposing factors.We illustrate an extremely rare case of a 62-year-old post-menopausal woman presenting with an acute myocardial infarction secondary to spontaneous dissection of the left anterior descending artery. Subsequent investigations did not reveal the presence of any co-morbidities.To the best of our knowledge, our patient is one of the oldest documented cases of spontaneous coronary artery dissection on record, and is notable for having no known underlying risk factors for development of spontaneous coronary artery dissection.Given the paucity of literature on spontaneous coronary artery dissection, particularly in postmenopausal women, we believe this case will provide further insight into the clinical presentation and management of this rare entity.Case presentationA 62-year-old previously healthy postmenopausal Hispanic woman presented with chest pain and was found to have an ST elevation myocardial infarction. Cardiac catheterization revealed a dissection in her left anterior descending artery. Revascularization was deferred; our patient received appropriate medical management and remained asymptomatic. A full panel of tests was done to exclude underlying connective tissue disorders and vasculitis. On subsequent follow-up, our patient continued to do well and all work-up was reported as negative.ConclusionWe describe the varied presentation and subsequent management of a case of spontaneous coronary artery dissection and highlight the importance of considering spontaneous coronary artery dissection as a differential diagnosis even in older, postmenopausal women.The consequences of a delay in diagnosis and appropriate management are associated with a high mortality and morbidity; hence we believe that reporting all cases of spontaneous coronary artery dissection, particularly in postmenopausal women, will add invaluable information to the limited literature on this rare condition.