Michael P. Siegenthaler

Incidence and Patterns of Adverse Event Onset During the First 60 Days After Ventricular Assist Device Implantation

BACKGROUND Although ventricular assist devices (VADs) provide effective treatment for end-stage heart failure, VAD support remains associated with significant risk for adverse events (AEs). To date there has been no detailed assessment of the incidence of a full range of AEs using standardized event definitions. We sought to characterize the frequency and timing of AE onset during the first 60 days of VAD support, a period during which clinical observation suggests the risk of incident AEs is high. METHODS A retrospective analysis was performed utilizing prospectively collected data from a single-site clinical database including 195 patients aged 18 or greater receiving VADs between 1996 and 2006. Adverse events were coded using standardized criteria. Cumulative incidence rates were determined, controlling for competing risks (death, transplantation, recovery-wean). RESULTS During the first 60 days after implantation, the most common AEs were bleeding, infection, and arrhythmias (cumulative incidence rates, 36% to 48%), followed by tamponade, respiratory events, reoperations, and neurologic events (24% to 31%). Other events (eg, hemolysis, renal, hepatic events) were less common (rates <15%). Some events (eg, bleeding, arrhythmias) showed steep onset rates early after implantation. Others (eg, infections, neurologic events) had gradual onsets during the 60-day period. Incidence of most events did not vary by implant era (1996 to 2000 vs 2001 to 2006) or by left ventricular versus biventricular support. CONCLUSIONS Understanding differential temporal patterns of AE onset will allow preventive strategies to be targeted to the time periods when specific AE risks are greatest. The AE incidence rates provide benchmarks against which future studies of VAD-related risks may be compared.

Preoperative chemotherapy for lung cancer does not increase surgical morbidity

BACKGROUND Preoperative chemotherapy (C+S) for non-small cell lung cancer (NSCLC) has increased in an attempt to improve survival. Patients receiving C+S potentially may have an increase in postoperative morbidity and mortality compared with surgery alone (S). We reviewed our experience with C+S and S in a tertiary referral center. METHODS Three hundred eighty consecutive patients underwent lobectomy or greater resection for NSCLC between August 1, 1996, and April 30, 1999: 335 patients (259 S; 76 C+S) were analyzed; 45 additional patients were excluded for prior NSCLC, other chemotherapy for other malignancy, or radiation. We compared morbidity and mortality overall, and by subset analysis (clinical stage, pathological stage, procedure, and by protocol use) for both C+S and S patients. RESULTS Demographics, comorbidities, and spirometry were similar. We noted no significant difference in overall or subset mortality or morbidity including pneumonia, acute respiratory distress syndrome, reintubation, tracheostomy, wound complications, or length of hospitalization. CONCLUSIONS C+S did not significantly affect morbidity or mortality overall, based on clinical stage, postoperative stage, or extent of resection. The potential for enhanced survival in resectable NSCLC justifies continued study of C+S.

Clinical Experience Using the Levitronix CentriMag System for Temporary Right Ventricular Mechanical Circulatory Support

BACKGROUND Short-term mechanical circulatory support may be lifesaving in patients with right ventricular (RV) failure related to post-cardiotomy cardiogenic shock (PCCS), cardiac transplantation (CTx), and long-term therapy with a left ventricular assist device (LVAD). This study evaluates our clinical experience using the CentriMag (Levitronix LLC, Waltham, Mass) system for temporary mechanical RV support. METHODS A retrospective review was performed of 29 patients (mean age, 57 +/- 14 years) in whom the CentriMag system was used for RV support from September 2005 to March 2008. RESULTS The indication for RV support was PCCS in 7 (24%), CTx in 10 (35%), and LVAD placement in 12 (41%). The mean support time was 8 +/- 8 days. The device was successfully weaned in 3 PCCS patients (43%), 7 CTx patients (70%), and 7 LVAD patients (58%). Complications included major infection (pneumonia, sepsis, or LVAD pocket infection) in 13 (45%), arrhythmia in 13 (45%), reoperation for bleeding in 10 (35%), stroke/encephalopathy in 3 (10%), and air embolism in 1 (3%). Early mortality (< 30 days or before discharge) occurred in 14 patients (48%) of which 9 (31%) died with the device in place. Late death occurred in 2 of 15 patients (13%) who survived to discharge. There were no device failures. CONCLUSIONS The CentriMag system provides effective temporary mechanical circulatory support for RV failure. Ease of implantation and a high rate of successful device weaning justify the use of the CentriMag system for temporary RV support.

The Jarvik 2000 is associated with less infections than the HeartMate left ventricular assist device

OBJECTIVES Device-related infections remain a considerable problem of left-ventricular support. We compared the device-related-infections between the HeartMate left ventricular assist device (LVAD) and the Jarvik 2000 permanent LVAD, a device with a novel retroauricular power-supply. METHODS Between December 2000 and September 2002 we implanted the HeartMate-vented, electrical-system in 11 patients and the permanent Jarvik 2000 in six patients. Total support time was 1626 patient-days (HeartMate, 26-271 days) versus 1246 patient-days (Jarvik 2000, 8-411 days). As potential risk factors for infection we analyzed age, preoperative hospital-days, total protein, cardiac index, maximal oxygen uptake, use of inotropes, LVAD risk-score-index and Aaronson-Mancini-score, intubation time, and intensive care unit stay. We used the Center of Disease Control definitions for surgical site infections. RESULTS HeartMate-patients were younger than Jarvik 2000 patients (46+/-13 versus 58+/-6 years, P=0.056), there were no other differences in the risk factors. Four HeartMate-patients needed late (>or=48 h) surgical revisions for bleeding/hematomas versus no revisions in the Jarvik 2000 patients. In the HeartMate-patients, there were seven (64%) driveline-infections, five (45%) device-pocket infections, and three (27%) bloodstream-infections, or 0.43 device-related infections/100 patient-days. Infections occurred early (34+/-31 days). Three patients required urgent transplantation due to bloodstream infection. There were no adverse outcomes in the HeartMate-group due to infection. In the Jarvik 2000 patients, there was one driveline-infection (16%) after 270 days of support (0.08 device-related infections/100 patient-days), significantly less than in the HeartMate-group (P=0.044). Driveline infections resolved with antibiotics and local wound care in the Jarvik 2000 patient, but only in one of seven HeartMate-patients. CONCLUSIONS Implantation of the Jarvik 2000 is associated with less device-related infections than the HeartMate-LVAD. The power-supply of the permanent Jarvik 2000 is suitable for long-term mechanical support.

Endovascular Aortic Arch Repair After Aortic Arch De-branching

PURPOSE Conventional surgical therapy of aortic arch aneurysms consists of aortic arch replacement requiring cardiopulmonary bypass and deep hypothermic circulatory arrest. This method is associated with significant morbidity and mortality, mainly due to neurologic complications and the sequelae of deep hypothermic circulatory arrest. Thus, it makes sense to work on developing less invasive surgical techniques. DESCRIPTION Surgical aortic arch de-branching is required before the supra-aortic vessels can be safely covered by an endovascular stent graft. We describe how the supra-aortic vessels can best be revascularized, followed by complete coverage of the aortic arch with endovascular stent grafts. EVALUATION We hereby present our case selection criteria, preoperative work-up, and surgical approach for aortic arch de-branching with supra-aortic revascularization, followed by complete coverage of the aortic arch by endovascular stent grafting. This techniques safeguards and pitfalls are described for a cohort of 26 patients. CONCLUSIONS Endovascular aortic arch repair after aortic arch de-branching has the potential to lower the morbidity and mortality rates in patients with aortic arch diseases.

Implantation of the permanent Jarvik-2000 left ventricular assist device: A single-center experience

OBJECTIVES We sought to evaluate the surgical results and effects of continuous support with the permanent Jarvik-2000 left ventricular assist device (LVAD). We report the early outcomes. BACKGROUND A shortage of transplant donors necessitates the testing of alternative treatments. The Jarvik-2000 is an axial flow pump with a percutaneous retro-auricular power connector, designed for permanent use. METHODS Patients with severe heart failure (HF), unsuitable for heart transplantation or conventional LVAD support, were offered implantation. The surgical approach included a left lateral thoracotomy. The device was implanted into the left ventricular apex on femoro-femoral bypass. It is set to allow pulsatile flow with an aortic valve opening. Anticoagulation is adjusted the same as for patients with a heart valve. RESULTS Between May 2001 and August 2001, we implanted the Jarvik-2000 in two patients with dilated cardiomyopathy and in one with cardiac amyloidosis, all with severe HF (cardiac index 1.8 +/- 0.3 l/m(2) per min). One patient required preoperative inotropic support. All patients did well, with no repeat operations or infections. Patients received 4.3 +/- 3.2 packed red blood cells and were intubated at 14 +/- 3 h, and the intensive care unit stay was 7.0 +/- 0.5 days. The cardiac index increased from 3.7 +/- 1.5 l/min per m(2) at 8,000 rpm to 5.9 +/- 2.9 l/min per m(2) at 12,000 rpm. All patients currently have mild hemolysis not requiring transfusion. The following postoperative events were recorded: a transient ischemic attack with complete recovery, a short re-intubation due to ventricular arrhythmia, loss of consciousness with a battery change while standing, knee-joint effusion after ergometry training, a minor wound problem and a short hospital re-admission due to dehydration. Patients were discharged home after 49 +/- 7 days; one has returned to work. All quality-of-life scores have improved. CONCLUSIONS The permanent Jarvik-2000 appears safe. It can be used for dilative or restrictive disease. The Jarvik-2000 might prove a valid option for the long-term treatment of patients with severe HF.

Destination therapy with a rotary blood pump and novel power delivery

OBJECTIVE We tested the hypothesis that a miniaturised axial flow pump with infection-resistant power delivery could improve longevity and quality of life (QOL) in advanced heart failure patients deemed unsuitable for transplantation. METHODS The study included all non-United States Jarvik 2000 patients (n=46), where a skull-pedestal-based power line was employed with the intention of long-term support. Patient age ranged from 29 to 80 years. Of the 46 patients, 42 were male. All were New York Heart Association (NYHA) IV predominantly with idiopathic dilated (n=22) or ischaemic (n=18) cardiomyopathy. The experience (2000-2008) included the learning curve of 10 centres. RESULTS The internal components are imperceptible. The power/control system is user friendly, allowing excellent QOL. There has been no pump malfunction. The Kaplan-Meier survival analysis is shown. The longest event-free survival is 7.5 years. Support exceeded 3 years in five cases. The cumulative experience exceeds 50 years. Three patients were transplanted, and two pumps were replaced at 90 and 203 days. Nineteen cases are ongoing (mean: 663 days), while 22 died during support (mean survival: 402 days), of which five from non-device-related diseases. Temporary local infection occurred in three pedestals, and there has been no pump infection. Incidence of thrombo-embolic events showed wide variation between centres. CONCLUSIONS From this learning-curve experience, both left ventricular assist device (LVAD) and power delivery are reliable and promising for destination therapy. Early mortality is similar to other studies and relates to the severity of illness. Pump infection has not occurred and prolonged event-free survival is clearly possible with expert medical management.

Implantation of the permanent Jarvik-2000 left-ventricular-assist-device: surgical technique

The Jarvik-2000 is an axial-flow left-ventricular-assist-device (LVAD) designed for permanent use. The power supply is provided by a cable plugged into a skull-pedestal mounted in the retro-auricular area. We describe the surgical technique and discuss potential and encountered problems.

The Jarvik 2000 Heart. Clinical validation of the intraventricular position

OBJECTIVE Heart failure is now a public health epidemic. Donor hearts are severely restricted in availability. Permanent mechanical circulatory support or bridge to myocardial recovery are emerging alternatives. After extensive laboratory experience we sought to evaluate the intraventricular Jarvik 2000 Heart in patients with endstage heart failure. METHODS The Jarvik 2000 Heart is a novel thumb-sized left ventricular assist device (LVAD) which is fitted within the apex of the native left ventricle. A vascular graft off loads this to the descending thoracic aorta. The pump rotor spins at between 8000 and 12,000 rpm providing 5-6 litres blood flow per minute. We have used the device with skull-mounted power delivery for seven permanent implants and trans-abdominal drive line for ten bridge-to-transplant patients. RESULTS All patients survived the operation. Three died from non-device related complications. Survivors had early resolution of heart failure with return to NYHA I/II. All had pulsatile circulation. The device was user-friendly and imperceptible to the patient. Both the pump and native left ventricle contributed to the cardiac output during exercise. Seven patients have been transplanted successfully. All explanted devices were free from thrombus formation. Two permanent implant patients left hospital as early as 3 weeks postoperatively. CONCLUSIONS The Jarvik 2000 is an effective user-friendly LVAD which allows early discharge from hospital. The intraventricular position has distinct advantages especially through absence of an inflow cannula. Synergy develops between the LVAD and native left ventricle. Early experience suggests that this may be a realistic LVAD to treat heart failure routinely in the outpatient setting.

Therapeutic implications of heat-induced lung injury

The safe and effective use of interstitial thermal therapy (ITT, radiofrequency ablation) for treatment of lung neoplasms was examined in a preclinical model. Lesions were reproducibly created in normal lung parenchyma and were affected by conductive heat loss via air and blood flow and the presence of bronchi. These observations of controlled injury to lung tissue suggest that clinical application would be appropriate and may yield advantages to selected patients with lung neoplasms (lung cancer, pulmonary metastases, etc.) or other pulmonary diseases.