Tanya Dutta

Transcatheter aortic valve replacement: current developments, ongoing issues, future outlook.

Since the first clinical implantation in 2002, transcatheter aortic valve implantation or transcatheter aortic valve replacement (TAVR) has become an established therapy in the treatment of symptomatic severe aortic stenosis in patients deemed too high risk for surgical aortic valve replacement. With over 50,000 implants performed in more than 40 countries, a large amount of clinical data have emerged in this rapidly growing field. Careful patient selection, systematic risk stratification, optimal valve sizing, meticulous procedural techniques, and complications management are all important elements to achieve good outcomes. However, several critical issues exist with TAVR that need to be addressed before it can become more widely adopted. Quality of life improvement and cost-effectiveness of TAVR, when compared to surgical aortic valve replacement, remain uncertain in lower risk patients. Stroke, paravalvular leak, vascular complication, bleeding, and heart block represent only a few of the key concerns in this therapy. Valve-in-valve procedures are becoming a novel application of transcatheter heart valve in the treatment of a degenerated bioprosthesis, and next generation heart valves that address some of these ongoing issues are currently under evaluation. Future prospective studies will allow us to refine this therapy and optimize outcomes in this high-risk patient population.

First percutaneous Micra leadless pacemaker implantation and tricuspid valve repair with MitraClip NT for lead-associated severe tricuspid regurgitation.

AIMS Pacemaker lead-associated severe tricuspid regurgitation (TR) can lead to right heart failure and poor prognosis. Surgery in these patients carries significant morbidities. We describe a successful treatment of symptomatic severe TR by leadless pacemaker implantation followed by tricuspid valve (TV) repair with the MitraClip NT. METHODS AND RESULTS A 71-year-old frail female with poor functional status, chronic atrial fibrillation and permanent pacemaker implantation in 2012 presented with symptomatic moderate-severe mitral regurgitation (MR) and severe TR with the pacemaker lead as the culprit. She was deemed extreme risk for double valve surgery and, because of her pacemaker dependency, the decision was to stage her interventions first with transcatheter mitral repair, then laser lead extraction and leadless pacemaker implantation to free the TV from tethering, then TV repair. An obstructive LAD lesion was identified and treated during mitral repair with the MitraClip NT. The Micra leadless pacemaker implantation and subsequent TV repair with the MitraClip NT were successful and the patients MR improved to mild and TR to moderate, respectively. CONCLUSIONS We report here a first successful transcatheter strategy to treat lead-associated severe TR by leadless pacemaker and MitraClip. Removing the pacemaker lead relieved leaflet tethering and improved the reparability of the TV.

Echocardiographic evaluation of the right ventricle: Clinical implications

Interest in evaluation of the right ventricle (RV) has increased recently. With the growth of new echocardiographic techniques and technology, there has been a corresponding increase in the ability to evaluate the RV, both qualitatively and quantitatively. Older echocardiographic techniques, such as right ventricular fractional area of change, tricuspid annular plane systolic excursion, and tissue S′, and newer echocardiographic techniques including 3‐dimensional evaluation and global longitudinal strain, can improve our evaluation of RV function. These techniques provide both diagnostic and prognostic data on a large variety of clinical diseases including pulmonary hypertension and congestive heart failure. With the continuing and exponential advances in technology, echocardiography is well poised to become the primary modality to evaluate the RV.

Afterload mismatch after transcatheter mitral valve repair with MitraClip for degenerative mitral regurgitation in acute cardiogenic shock: Afterload Mismatch in MitraClip Repair

Acute afterload mismatch after surgery for mitral regurgitation (MR) with transient left ventricular dysfunction is well known, but not described after transcatheter mitral valve repair with MitraClip, except in functional MR and cardiomyopathy. MitraClip to manage acute severe MR and cardiogenic shock has also been rarely reported. We report here a 77‐year‐old female who presented with acute severe degenerative MR from a flail posterior leaflet, with cardiogenic shock requiring intra‐aortic balloon pump support. She was medically stabilized and underwent successful MitraClip repair with mild residual MR, but developed acute afterload mismatch and severe left ventricular dysfunction and shock 24 hr after her procedure. Patient was medically managed with intra‐aortic balloon pump and inotropic support. She subsequently fully recovered with normal ventricular function and was discharged after 14 days. Patient remained asymptomatic in NYHA I functional class 9 months after MitraClip repair, with mild residual MR and normal ventricular function. MitraClip repair in patients with acute severe degenerative MR and cardiogenic shock is a less invasive and potentially safer alternative to open surgery, but acute afterload mismatch may occur and requires prompt diagnosis and management for a successful outcome.

Cavitation phenomenon: a novel echocardiographic finding in pump thrombosis.

Fig. 1. Modified parasternal long-axis view showing bubbles originating from inflow cannula of the left ventricular assist device. A 38-year-old woman with peripartum cardiomyopathy with persistently reduced left ventricular function after Heartmate II left ventricular assist device (LVAD) implantation 2 months earlier presented for evaluation of her LVAD alarms because she noted reduced pump speed and pulsatility index. On physical examination, her Doppler blood pressure was 84 mm Hg. Physical examination was significant for volume overload and cool extremities. Her laboratory results were significant for anemia (hemoglobin 8.6 g/dL), bilirubin 0.5 mg/dL, therapeutic international normalized ratio (2.58), elevated lactate dehydrogenase (782 U/L, normal 125e220 U/L), and reduced haptoglobin (!8 mg/dL, normal 13e281 mg/dL). These findings were concerning for malfunction of the LVAD, and a 2-dimensional echocardiogram was obtained, which showed severely dilated LV with severe diffuse hypokinesis and reduced systolic function. Midway through the study, numerous bubbles originating from the inflow cannula appeared in the LV cavity and aorta (Figs. 1e3; Online Videos 1 and 2). No echodensities were present in the right atrium or right ventricle. Continuous and pulse-wave Doppler assessment for increased velocity of flow across inflow and outflow cannulae were limited by suboptimal angle and poor imaging windows. Echocardiographic ramp study done subsequently to evaluate for LVAD thrombosis was suspicious for pump thrombosis (LVend-diastolic dimension slope 0.18; pulsatility index slope 0.20; power slope 0.64). Computerized tomographic angiography revealed a patent inflow conduit at its origin and no definite thrombus but with occlusion along the entire course of the

Echocardiography in the Evaluation of Pulmonary Embolism

Pulmonary embolism is a major cause of mortality. Acute pulmonary embolism also encompasses a wide clinical spectrum of severity, ranging from asymptomatic silent disease to hemodynamic instability and shock. Echocardiography is a useful modality to improve treatment strategies for pulmonary embolus. Echocardiography plays a role in risk stratification at the time of diagnosis. The evaluation of the right ventricle (RV) has evolved over time. RV variables evaluated by echocardiography include RV size, RV/left ventricular ratio, RV fractional area of change, tricuspid annular plane systolic excursion, RV systolic pressure, and RV Tei index. It has also been used in determining treatment strategies and following the success of treatment. Multiple echocardiographic criteria have been studied to improve risk stratification and outcomes from pulmonary embolism. Further studies are needed to assess the appropriate quantitative echocardiographic parameters.