Pranav Loyalka

Use of an Intrapericardial, Continuous-Flow, Centrifugal Pump in Patients Awaiting Heart Transplantation

Background— Contemporary ventricular assist device therapy results in a high rate of successful heart transplantation but is associated with bleeding, infections, and other complications. Further reductions in pump size, centrifugal design, and intrapericardial positioning may reduce complications and improve outcomes. Methods and Results— We studied a small, intrapericardially positioned, continuous-flow centrifugal pump in patients requiring an implanted ventricular assist device as a bridge to heart transplantation. The course of investigational pump recipients was compared with that of patients implanted contemporaneously with commercially available devices. The primary outcome, success, was defined as survival on the originally implanted device, transplantation, or explantation for ventricular recovery at 180 days and was evaluated for both noninferiority and superiority. Secondary outcomes included a comparison of survival between groups and functional and quality-of-life outcomes and adverse events in the investigational device group. A total of 140 patients received the investigational pump, and 499 patients received a commercially available pump implanted contemporaneously. Success occurred in 90.7% of investigational pump patients and 90.1% of controls, establishing the noninferiority of the investigational pump (P<0.001; 15% noninferiority margin). At 6 months, median 6-minute walk distance improved by 128.5 m, and both disease-specific and global quality-of-life scores improved significantly. Conclusions— A small, intrapericardially positioned, continuous-flow, centrifugal pump was noninferior to contemporaneously implanted, commercially available ventricular assist devices. Functional capacity and quality of life improved markedly, and the adverse event profile was favorable. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00751972.

A prospective feasibility trial investigating the use of the Impella 2.5 system in patients undergoing high-risk percutaneous coronary intervention (The PROTECT I Trial): initial U.S. experience

OBJECTIVES We sought to evaluate the safety and feasibility of the Impella 2.5 system (Abiomed Inc., Danvers, Massachusetts) in patients undergoing high-risk percutaneous coronary intervention (PCI). BACKGROUND The Impella 2.5 is a miniaturized percutaneous cardiac assist device, which provides up to 2.5 l/min forward flow from the left ventricle into the systemic circulation. METHODS In a prospective, multicenter study, 20 patients underwent high-risk PCI with minimally invasive circulatory support employing the Impella 2.5 system. All patients had poor left ventricular function (ejection fraction <or=35%) and underwent PCI on an unprotected left main coronary artery or last patent coronary conduit. Patients with recent ST-segment elevation myocardial infarction or cardiogenic shock were excluded. The primary safety end point was the incidence of major adverse cardiac events at 30 days. The primary efficacy end point was freedom from hemodynamic compromise during PCI (defined as a decrease in mean arterial pressure below 60 mm Hg for >10 min). RESULTS The Impella 2.5 device was implanted successfully in all patients. The mean duration of circulatory support was 1.7 +/- 0.6 h (range: 0.4 to 2.5 h). Mean pump flow during PCI was 2.2 +/- 0.3 l/min. At 30 days, the incidence of major adverse cardiac events was 20% (2 patients had a periprocedural myocardial infarction; 2 patients died at days 12 and 14). There was no evidence of aortic valve injury, cardiac perforation, or limb ischemia. Two patients (10%) developed mild, transient hemolysis without clinical sequelae. None of the patients developed hemodynamic compromise during PCI. CONCLUSIONS The Impella 2.5 system is safe, easy to implant, and provides excellent hemodynamic support during high-risk PCI. (The PROTECT I Trial; NCT00534859).

The Percutaneous Ventricular Assist Device in Severe Refractory Cardiogenic Shock

OBJECTIVES We evaluated the efficacy and safety of the percutaneous ventricular assist device (pVAD) in patients in severe refractory cardiogenic shock (SRCS) despite intra-aortic balloon pump (IABP) and/or high-dose vasopressor support. BACKGROUND SRCS is associated with substantial mortality despite IABP counterpulsation. Until recently, there was no rapid, minimally invasive means of providing increased hemodynamic support in SRCS. METHODS A total of 117 patients with SRCS implanted with TandemHeart pVAD (CardiacAssist, Inc., Pittsburgh, Pennsylvania) were studied, of whom 56 patients (47.9%) underwent active cardiopulmonary resuscitation immediately before or at the time of implantation. Data was collected regarding clinical characteristics, hemodynamics, and laboratory values. RESULTS Eighty patients had ischemic and 37 patients had nonischemic cardiomyopathy. The average duration of support was 5.8 ± 4.75 days. After implantation, the cardiac index improved from median 0.52 (interquartile range [IQR]: 0.8) l/(min·m(2)) to 3.0 (IQR:0.9) l/(min·m(2)) (p < 0.001). The systolic blood pressure and mixed venous oxygen saturation increased from 75 (IQR:15) mm Hg to 100 (IQR:15) mm Hg (p < 0.001) and 49 (IQR:11.5) to 69.3 (IQR:10) (p < 0.001), respectively. The urine output increased from 70.7 (IQR: 70) ml/day to 1,200 (IQR: 1,620) ml/day (p < 0.001). The pulmonary capillary wedge pressure, lactic acid level, and creatinine level decreased, respectively, from 31.53 ± 10.2 mm Hg to 17.29 ± 10.82 mm Hg (p < 0.001), 24.5 (IQR: 74.25) mg/dl to 11 (IQR: 92) mg/dl (p < 0.001), and 1.5 (IQR: 0.95) mg/dl to 1.2 (IQR: 0.9) mg/dl (p = 0.009). The mortality rates at 30 days and 6 months were 40.2% and 45.3%, respectively. CONCLUSIONS The pVAD rapidly reversed the terminal hemodynamic compromise seen in patients with SRCS refractory to IABP and vasopressor support.

Extracorporeal Membrane Oxygenation as a Bridge to Emergency Heart-Lung Transplantation in a Patient With Idiopathic Pulmonary Arterial Hypertension

Lung transplantation with or without cardiac transplantation offers the only hope of long-term, symptom-free survival for patients with advanced idiopathic pulmonary arterial hypertension. We describe a patient who underwent an emergency pulmonary embolectomy. During surgery, it was discovered that the patient had idiopathic pulmonary arterial hypertension. After the patient was weaned from cardiopulmonary bypass, pulmonary hypertension caused right-sided heart failure, and a right ventricular assist device was inserted to compensate. Because of profound bleeding from the endotracheal tube, the patient was placed on extracorporeal membrane oxygenation in the hope of bridging the patient to heart-lung transplantation. Extracorporeal membrane oxygenation was required for 10 days until a donor heart and lung became available. The patient recovered from the transplant operation and was discharged home 76 days later.

A Less Invasive Approach to Axial Flow Pump Insertion

BACKGROUND Implantation of a HeartMate II or a Jarvik 2000 FlowMaker left ventricular assist system (LVAS) usually involves a mid-line sternotomy and the use of cardiopulmonary bypass (CPB). In patients with numerous co-morbid conditions, however, surgical trauma may be minimized by implanting the LVAS via a minimally invasive approach, preferably without CPB. METHODS In 6 patients with end-stage heart failure and other serious co-morbidities, we implanted a HeartMate II (n = 3) or a Jarvik 2000 FlowMaker (n = 3) LVAS via a right mini-thoracotomy and a left sub-costal incision. Patients included 3 men and 3 women with a mean age of 41 years. In 3 cases, the LVAS was implanted without CPB. RESULTS After a mean follow-up period of 6 months, 5 patients are alive and well and on the transplant waiting list. Seven months after LVAS implantation, the remaining patient developed a hemorrhagic stroke necessitating Jarvik 2000 replacement with a new pump of the same type. CONCLUSIONS In this small series, the combined sub-costal and mini-thoracotomy incision proved safe and technically feasible. It may be useful for other LVAS candidates who have serious co-morbidities that preclude traditional implant operations.

Use of the Percutaneous Left Ventricular Assist Device in Patients with Severe Refractory Cardiogenic Shock as a Bridge to Long-term Left Ventricular Assist Device Implantation

BACKGROUND For patients with persistent cardiogenic shock refractory to intraaortic balloon pump (IABP) support, there are only limited means of resuscitation and bridging to surgical left ventricular assist device (LVAD) implantation. Extracorporeal membrane oxygenation and emergency surgical approaches have been attempted but are associated with significant morbidity and mortality. We evaluated the efficacy of a percutaneous left ventricular assist device (PVAD) as a bridge to LVAD implantation in patients in cardiogenic shock refractory to IABP and pressor support. METHODS Between May 2003 and April 2006, at our institution, 18 patients in severe refractory cardiogenic shock received a PVAD as a bridge to LVAD placement or orthotopic heart transplantation. Six patients had ischemic cardiomyopathy, and 12 had nonischemic cardiomyopathy. At the time of PVAD placement, 17 were receiving IABP support, and 10 were undergoing cardiopulmonary resuscitation. RESULTS The mean duration of PVAD support was 4.2 +/- 2.5 days. During this time, the cardiac index improved from 0.86 +/- 0.66 to 2.50 +/- 0.93 liters/min/m2 (p < 0.001), systolic blood pressure improved from 72 +/- 11 to 98 +/- 15 mm Hg (p = 0.001), and systemic mixed venous oxygenation improved from 37 +/- 7 to 62 +/- 6 mm Hg (p < 0.001). We terminated life support in 4 of the 18 patients before LVAD placement; 14 were successfully bridged to LVAD or heart transplantation. The mortality rate was 27% at 30 days and 33% at 6 months. There were no PVAD-associated deaths. CONCLUSION In patients with terminal hemodynamic collapse, PVAD support is an effective bridging therapy to LVAD and appears to be a viable alternative to other invasive methods of support.

Current status of percutaneous ventricular assist devices for cardiogenic shock

Purpose of review Percutaneous ventricular assist devices (pVADs) are being increasingly used in patients with cardiogenic shock. They offer a means of instituting rapid and adequate cardiac support in patients with cardiogenic shock unresponsive to inotropes/vasopressors and intraaortic balloon pumps (IABPs). However, there is considerable debate on the appropriate use of these devices given the difficulty of conducting randomized trials in patients with cardiogenic shock, lack of clear guidelines on indications, device selection, and cost-effective care of patients implanted with these devices. Recent findings Several centers have recently reported data on the use of these devices for cardiogenic shock in a variety of different settings, including myocardial ischemia and its complications, high-risk percutaneous coronary intervention, myocarditis, and refractory arrhythmias. Recent randomized trials have compared the use of IABP with different pVADs evaluating hemodynamic outcomes as well as short-term mortality. Summary We review the current evidence on the use of pVADs (Tandemheart pVAD, Impella, percutaneous extracorporeal membrane oxygenation), their indications, relative merits, and adverse effects, and discuss the current approach to the appropriate use of pVADs in patients with cardiogenic shock. We also propose an algorithm for device selection tailored to each patients needs based on severity of cardiogenic shock, amount of support needed, and the overall clinical scenario.

Techniques and complications of TandemHeart ventricular assist device insertion during cardiac procedures.

Patients with heart failure and profound cardiogenic shock, who are unresponsive to vasopressors and intra-aortic balloon pump insertion, have few options except for mechanical cardiac support with a ventricular assist device. The TandemHeart is a new assist device that may be percutaneously or surgically inserted. We review techniques for percutaneous and intraoperative placement of the TandemHeart, including detailed descriptions of its insertion. Additionally, we present the most common complications associated with the percutaneous or operative approaches and suggest ways to avoid these complications. Whether placed percutaneously or surgically, the TandemHeart can provide adequate hemodynamic support for heart failure patients. If the device is placed by surgeons in the operating room, there must be strict adherence to protocols and de-airing techniques. Complications may occur with either insertion technique, so knowledge of the most common types of complications and their prevention is necessary.

Percutaneous ventricular assist device support during off-pump surgical coronary revascularization.

Intraaortic balloon pump counterpulsation has been used for mechanical circulatory support in cardiogenic shock patients, but percutaneous left ventricular assist devices can provide superior circulatory support in the same group of patients. We describe the case of a patient in cardiogenic shock after a myocardial infarction. A percutaneous ventricular assist device was used to provide immediate active hemodynamic support, and, because the patients condition necessitated surgical revascularization, percutaneous left ventricular assist device support was continued during off-pump coronary artery bypass.

Percutaneous left ventricular assist device complicated by a patent foramen ovale: importance of identification and management.

Recently, the TandemHeart® percutaneous left ventricular assist device (pVAD) has become available as a means to both resuscitate and support patients in cardiogenic shock pending myocardial recovery or definitive surgical or percutaneous intervention. Hypoxia during pVAD support may arise from multiple pulmonary etiologies, including pulmonary edema and mechanisms resulting in right‐to‐left shunting. We report two cases of patients supported by pVADs in who patent foramen ovale (PFO) present as right‐to‐left shunts following initiation of TandemHeart® support. A review of the mechanisms and hemodynamics resulting in PFO patency during pVAD support as well as suggestions for management are presented.