Mechanical Circulatory Support in TAVR Tied to Worse Outcomes, Higher Costs

Use of mechanical circulatory support (MCS) devices in patients undergoing TAVR is associated with increased in-hospital mortality, more procedural complications, and higher hospitalization costs, according to a study published online August 31, 2015, ahead of print in the American Journal of Cardiology.

The findings “should raise concerns about [the] utility of MCS devices during [TAVR] in this prohibitive-surgical-risk population,” write Apurva O. Badheka, MD, of the Everett Clinic (Everett, WA), and colleagues.

The researchers looked at data from the Nationwide Inpatient Sample on 1,794 TAVR procedures performed in the United States in 2011 and 2012; 10.6% involved MCS. Support included cardiopulmonary bypass in 71.6%, intra-aortic balloon pumps in 18.9%, extracorporeal membrane oxygenation in 7.4%, and percutaneous ventricular assist devices in 2.1%.

Patients who received MCS were more likely to undergo transapical TAVR and PCI and to have acute MI, cardiac arrest, and cardiogenic shock compared with those who did not use an MCS device. They also were younger and more likely to be female and had lower rates of congestive heart failure, chronic obstructive pulmonary disease, and PAD.

MCS use was associated with higher rates of in-hospital mortality and procedural complications, a longer mean hospital stay, and an increase in hospitalization cost.

Moreover, MCS patients were more likely to require open heart surgery (22.0% vs 0.5%) and to have acute renal failure requiring dialysis and vascular, cardiac, respiratory, and infectious complications (P < .01 for all).

After multivariate adjustment, MCS use was an independent predictor of in-hospital mortality (OR 3.45; 2.57-4.61) and procedural complications (OR 3.27; 95% CI 2.77-3.87). Propensity score-matched analysis yielded similar findings.

Limited Data on MCS Use in TAVR

Dr. Badheka and colleagues note that the PARTNER trial excluded patients who required MCS devices. However, in everyday practice, “these devices can be used preemptively in patients with severely impaired left ventricular function, severe mitral regurgitation, [and] slow recovery/stunning from rapid ventricular pacing,” as well as those taking high doses of pressors and those undergoing concomitant high-risk PCI, they say.

Also, the study authors suggest, “MCS may be required emergently in cases of life-threatening periprocedural complications such as cardiac tamponade, severe paravalvular regurgitation, annulus rupture, ventricular perforation, medically refractory hemodynamic instability or cardiogenic shock, ventricular arrhythmias, and coronary obstruction.”

Furthermore, a consensus statement on percutaneous hemodynamic support published in April by several professional cardiovascular societies “recognized high-risk patients with valvular diseases as a rapidly emerging population which may benefit from short-term use of MCS devices,” while acknowledging the limited data available to guide clinicians in this area, Dr. Badheka and colleagues write.

The current study lacks data on the indications for and timing and duration of MCS use; hemodynamic and echocardiographic variables; and whether use was planned or emergent, the researchers acknowledge. Yet the findings still “should spark a debate over elective use of these devices with [TAVR], especially because a benefit of their prophylactic use in other settings including PCI has not been demonstrated in randomized clinical trials,” they say. “Further safety and efficacy data regarding the use of MCS devices from the contemporary TVT registry are therefore warranted and should be explored.”