We examined the TandemHeart's effect on cardiac index, central venous pressure, mixed venous oxygen saturation, creatinine, mean arterial pressure, urine output, and 30-day mortality rate in 5 heart-failure patients (2 with nonischemic and 3 with ischemic cardiomyopathy; mean preoperative left ventricular ejection fraction, 0.17 ± 0.056). Two patients were undergoing cardiopulmonary resuscitation when the device was inserted. The average duration of TandemHeart support was 7.6 ± 3.2 days; all patients were successfully bridged to transplantation.
The TandemHeart improved the cardiac index (1.9 ± 0.3 vs 3.5 ± 0.8 L/[min·m2], P= 0.01), mean arterial pressure (69 ± 12.5 vs 91 ± 4.3 mmHg, P=0.009), mixed venous oxygen saturation (45.4 ± 14.3 vs 71.4 ± 7.5, P=0.009), and urine output (1,861 ± 988 vs 4,314 ± 1,346 mL/hr, P=0.01). The device decreased central venous pressure (21.2 ± 7.4 vs 12.8 ± 5.9 mmHg, P=0.02) and pressor requirements (2.4 ± 1.1 vs 1.0 ± 0.7 agents, P=0.02). Average long-term follow-up after heart transplantation was 8.4 ± 9.9 months, with no deaths.
We conclude that the TandemHeart can provide hemodynamic support for patients with profound, refractory cardiogenic shock. Furthermore, the device can bridge patients to cardiac transplantation and can be placed percutaneously, without invasive surgery.