Echocardiographic Dyssynchrony and Health Status Outcomes From Cardiac Resynchronization Therapy Insights From the PROSPECT Trial

ObjectivesThis study sought to assess the prognostic utility of echocardiographic dyssynchrony for health status improvement after cardiac resynchronization therapy (CRT).BackgroundEchocardiographic measures of dyssynchrony have been proposed for patient selection for CRT, but prospective validation studies are lacking.MethodsA prospective cohort of 324 patients from 53 centers with moderate to severe heart failure, left ventricular dysfunction, QRS ≥130 ms, and available echocardiographic and health status information were identified from the PROSPECT (Predictors of Response to Cardiac Re-Synchronization Therapy) trial, which evaluated the prognostic utility of dyssynchrony measures in CRT recipients. The association of 12 echocardiographic dyssynchrony parameters with 6-month improvement in health status, as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), was assessed both as a continuous variable and by responder status (ΔKCCQ ≥+10 points reflecting moderate to large improvement).ResultsOf 12 pre-defined dyssynchrony parameters, only 3 were consistently reported: interventricular mechanical delay (IVMD), left ventricular filling time relative to the cardiac cycle (LVFT), and left ventricular pre-ejection interval. After multivariable adjustment, IVMD (+5.18, 95% confidence interval [CI]: +0.76 to +9.60; p = 0.02) and LVFT (+5.19, 95% CI: +0.45 to +0.94; p = 0.03) were independently associated with 6-month improvements in KCCQ. Patients with 6-month improvements in KCCQ had lower subsequent mortality (adjusted hazard ratio [HR] for each 5-point improvement: 0.83; 95% CI: 0.72 to 0.93; p = 0.03). Additionally, IVMD was associated with CRT responder status (for ΔKCCQ ≥+10 points: odds ratio [OR]: 1.85; 95% CI: 1.12 to 3.05; p = 0.03), whereas LVFT was not (OR: 1.63; 95% CI: 0.85 to 3.11; p = 0.14). Patients classified as health status responders had a 76% lower subsequent risk of all-cause mortality (adjusted HR: 0.24; 95% CI: 0.07 to 0.84; p = 0.03).ConclusionsThe presence of pre-implantation IVMD and LVFT was associated with 6-month health status improvement, and IVMD was associated with a significant CRT response. These echocardiographic factors may help clinicians counsel patients regarding their likelihood of symptomatic improvement with CRT. (PROSPECT: Predictors of Response to Cardiac Re-Synchronization Therapy; NCT00253357

Cardioembolic Stroke in Atrial Fibrillation-Rationale for Preventive Closure of the Left Atrial Appendage

Atrial fibrillation is the most common cardiac arrhythmias, and a major cause of morbidity and mortality due to cardioembolic stroke. The left atrial appendage is the major site of thrombus formation in non-valvular atrial fibrillation. Loss of atrial systole in atrial fibrillation and increased relative risk of associated stroke point strongly toward a role for stasis of blood in left atrial thrombosis, although thrombus formation is multifactorial, and much more than blood flow irregularities are implicated. Oral anticoagulation with vitamin-K-antagonists is currently the most effective prophylaxis for stroke in atrial fibrillation. Unfortunately, this treatment is often contraindicated, particularly in the elderly, in whom risk of stroke is high. Moreover, given the risk of major bleeding, there is reason to be skeptical of the net benefit when warfarin is used in those patients. This work reviews the pathophysiology of cardioembolic stroke and critically spotlights the current status of preventive anticoagulation therapy. Various techniques to exclude the left atrial appendage from circulation were discussed as a considerable alternative for stroke prophylaxis

Transesophageal echocardiographic guidance of transcatheter closure of the aortic valve in a patient with left ventricular assist device-related severe aortic regurgitation

A 68-year-old man with a severe ischemic cardiomyopathy underwent left ventricular assist device (LVAD) implantation (Heart Mate II device) for destination therapy. He presented 49 months after LVAD implantation with worsening heart failure symptoms and new severe aortic regurgitation. Given high risk for both surgical and transcatheter aortic valve replacement, he was admitted for transcatheter closure of the aortic valve under transesophageal echocardiographic (TEE) guidance. TEE imaging revealed severe aortic regurgitation (Fig. 1A and B and Videos 1 and 2). Under TEE and fluoroscopic guidance, a 25 mm Amplatzer cribriform atrial septal defect closure device was advanced across the aortic valve (Fig. 1C and D and Videos 3 and 4). Immediately after device deployment, TEE revealed a well-seated device with complete aortic valve closure and trivial aortic regurgitation (Fig. 2A, B, C and D and Videos 5, 6, 7 and 8). Subsequent transthoracic echocardiograms obtained from 74 to 172 days after the procedure revealed no residual aortic regurgitation. The patient awoke with diffuse urticaria 244 days after the procedure and died en route to the emergency department, presumably secondary to a systemic allergic reaction. De novo aortic regurgitation is increasingly recognized in patients with LVADs (1). TEE-guided transcatheter aortic valve closure is an option in these high-risk patients (2)

Clinical factors associated with left ventricular ejection fraction disparity in patients with left ventricular dysfunction undergoing multimodality imaging.

Drug and device therapy for heart failure is increasingly determined based on left ventricular ejection fraction. Significant disparity frequently exists between echocardiographic and nuclear scintigraphic techniques, even when testing is performed nearly simultaneously in clinically stable patients. In 119 patients with left ventricular dysfunction who underwent both echocardiography and stress testing with nuclear imaging within seven days (but with significant disparity in reported left ventricular ejection fraction), we identified four clinical variables which were associated with left ventricular ejection fraction difference. These clinical variables included atrial fibrillation, left ventricular hypertrophy, severe mitral regurgitation and paced rhythm