Amit Pawale

Tissue Reaction to Porcine Intestinal Submucosa (CorMatrix) Implants in Pediatric Cardiac Patients: A Single-Center Experience

BACKGROUND Decellularized porcine small intestine submucosa (CorMatrix, Atlanta, GA) patches have been used in the repair of congenital heart malformations. Tissue reaction to the material may create hemodynamic dysfunction and necessitate explantation. We reviewed our series of congenital cardiac patients who had a reoperation after the implantation of CorMatrix patches. METHODS Medical records of pediatric cardiac patient who received CorMatrix patches and those of patients who underwent reoperation were reviewed. Routine histologic sections of explanted CorMatrix specimens were examined. RESULTS Of 25 patients who had received CorMatrix patches during cardiac operations at our institution, 6 patients had undergone reoperations. All patients had hemodynamically significant lesions at the site of the CorMatrix implantation. Explanted specimens were associated with an intense inflammatory reaction consisting of numerous eosinophils, histiocytes, and plasma cells, with accompanying granulation tissue and fibrosis. CONCLUSIONS Reaction to implanted CorMatrix patches may cause hemodynamic dysfunction and produce an intense, predominantly eosinophilic inflammatory response with developing fibrosis. Although our report is limited to a small sample of congenital cardiac patients, one should take precautions in its use in pediatric cardiac patients, and long-term follow-up is warranted.

Implantable left ventricular assist devices as initial therapy for refractory postmyocardial infarction cardiogenic shock

OBJECTIVES Recently, the initial therapy for refractory cardiogenic shock has largely been based on use of short-term mechanical devices with later conversion to durable options. The premise is that such patients cannot tolerate cardiopulmonary bypass and the extended surgery needed for implantable left ventricular assist device (LVAD) placement. We have adopted an alternative strategy to implant long-term LVADs as the initial device therapy in such patients. METHODS Over a 3 year period, we used implantable LVADs (Jarvik 2000, one; Ventrassist, one; Heartmate XVE, two; and Heartmate II, nine) in 13 patients (11 men and two women; mean age 54 years) with postmyocardial infarction shock without prior use of a short-term LVAD. The median time interval from myocardial infarction to LVAD implantation was 3.5 days. Eight patients were on a ventilator, two had unknown neurological status and four had suffered cardiac arrest in the preceding 24 h. Two had prior coronary artery bypass graft. Nine had received dual antiplatelet therapy postmyocardial infarction. The mean laboratory value of creatinine was 1.5 mg/dl, alanine aminotransferase 748 U/l, international normalized ratio 1.5 and lactate 3.2 mmol/l. One procedure was carried out off pump; for the others, the mean cardiopulmonary bypass time was 72 min. Right ventricular assist devices were used in two cases and were later explanted. RESULTS One patient died of progressive multiorgan failure. All others survived to hospital discharge. There were no re-explorations for bleeding or major infectious complications; two patients had perioperative stroke. The median duration of mechanical ventilation, intensive care unit stay and hospital stay was 3, 9 and 18 days, respectively. At 1 year, of the 12 survivors, eight have since had heart transplant, one patient underwent device explant, two remained alive on support and one died 7 months post-LVAD. CONCLUSIONS Our data challenge the notion that patients in refractory cardiogenic shock are too ill to tolerate immediate placement of implantable LVADs. Despite the surgical challenges, a one-stop implantable LVAD approach for cardiogenic shock is feasible and may offer unique advantages over the bridge-to-bridge approach because it avoids the incremental costs, hospitalization and morbidity associated with repeated interventions.

Direct Access Implantation of a Melody Valve in Native Mitral Valve: A Hybrid Approach in the Presence of Extensive Mitral Annular Calcification

76-year-old woman presented with congestive heart Afailure. Transthoracic echocardiogram showed severe mitral regurgitation and moderate mitral stenosis with a mean gradient of 8 mm Hg as a result of inflow obstruction in the setting of extensive mitral annular calcium with severe tricuspid regurgitation and severe pulmonary hypertension. The preoperative coronary angiogram and the computed tomography scan showed horseshoe-shaped severe mitral annular calcium (Figs 1A [arrows], 1B). Intraoperative transesophageal echocardiogram confirmed the mitral annular calcium (Fig 1D), and there was severe mitral regurgitation (Fig 1C). Annular decalcification and mitral valve replacement would carry an extreme risk of atrioventricular groove disruption. Hence sutureless implantation of a Melody valve (Medtronic, Inc, Minneapolis, MN) into the native mitral valve using the leaflet and annular calcium as a landing zone was considered. Cardiopulmonary bypass

Bench Mitral Valve Repair of Donor Hearts Before Orthotopic Heart Transplantation

Cardiac transplantation remains the most effective therapy for end-stage heart failure in appropriate candidates, with a median posttransplant survival of 10 years. At any given point of time there are ≈3000 candidates on the heart transplant waiting list in the United States with annual mortality on the waiting list ≈15%. The number of heart transplants performed in the United States per year has been fairly constant at ≈2500. In spite of this, many donor hearts remain unused. Bench repair of mitral valves remains rarely practiced and significant mitral valve regurgitation (MR) remains a standard contraindication to use of a donor heart. A 53-year-old male donor who had a cerebral infarct became available for a 61-year-old man with blood group O who received left ventricular assist device, Heartmate II (Thoratec, Pleasanton, CA), for decompensated dilated cardiomyopathy. The donor coronary angiogram was normal. Donor transthoracic echocardiogram (TTE) showed inferior wall hypokinesis, interventricular septum 1.15 cm, …

Selective implantation of durable left ventricular assist devices as primary therapy for refractory cardiogenic shock

Objective: Surgical therapy for refractory primary cardiogenic shock is largely based on emergent placement of extracorporeal membrane oxygenation or short‐term ventricular assist devices. We have adopted a strategy of routine implantation of durable left ventricular assist devices (LVAD) as initial therapy for refractory cardiogenic shock, in patients who are potential candidates for heart transplantation, and report our experience. Methods: Retrospective review of 43 consecutive patients with refractory shock caused by acute myocardial infarction (n = 21) or acute decompensated heart failure (n = 22) who were treated with primary implantation of a durable LVAD in a single institution. Results: All patients received durable LVAD (axial flow, n = 37; centrifugal, n = 4; pulsatile, n = 2), with concurrent placement of right ventricular assist device (RVAD) in 5 patients (12%). One patient had delayed RVAD implantation. Mean operative time was 362 minutes and mean cardiopulmonary bypass time was 94 minutes. Twenty patients underwent concurrent cardiac procedures. Major early adverse events included operative mortality 14% (6/43), reoperation for bleeding 7% (3/43), and stroke 4.7% (2/43). Median time on mechanical ventilation was 3.5 days, ICU stay 9 days, and hospital stay 25 days. Kaplan‐Meier survival was 82.7 ± 6.0% at 6 months and 73.9 ± 8.0% at 12 months. Using competing analysis, the cumulative incidence of transplantation was 10.3 ± 5.0% at 6 months and 30.8 ± 7.9% at 1 year. Conclusions: Our data challenge the notion that patients in refractory cardiogenic shock are best served by an initial period of stabilization with temporary devices. Primary implantation of durable LVADs in cardiogenic shock can yield good midterm outcomes and may have potential benefits.

Accessory Mitral Valve Leaflet

n 89-year-old-man with severe symptomatic aortic Astenosis was found to have an accessory mitral valve leaflet causing systolic anterior motion on the preoperative echocardiogram. Intraoperative transesophageal echocardiography showed the presence of a 2-cm long and 0.4-cm thick membranelike structure (accessory mitral leaflet) attached to the ventricular side of the anterior mitral leaflet (Figs 1A-1C; Ao 1⁄4 aorta, LA 1⁄4 left

Technique for implantation of HeartMate II left ventricular assist device with concurrent mitral and tricuspid valve repair

A 50-year-old male with end-stage cardiomyopathy had been on the transplant waiting list as UNOS status 1b and was recently admitted to hospital with decompensated heart failure (Video 1). His recent transthoracic echocardiogram showed dilated left ventricle with severe dysfunction, severe mitral valve regurgitation and severe tricuspid valve regurgitation. He was in INTERMACS class II and was referred for mechanical circulatory support as a bridge to transplant.

Balloon in the left ventricular outflow tract: A surgical technique for the calcified unclampable aorta with aortic insufficiency

Calcified ascending aorta with severe aortic insufficiency (AI) is a unique problem. Clamping a heavily calcified aorta carries a major risk of stroke. To achieve adequate systemic cooling for deep hypothermic circulatory arrest (DHCA) without aortic clamping in the setting of severe AI is a difficult challenge. In such a scenario, if ventricular fibrillation occurs, the left ventricle (LV) can distend despite the LV vent, which is typically placed through the right superior pulmonary vein (RSPV). This can lead to subendocardial ischemia and myofibrillar disruption, with subsequent myocardial dysfunction. Ventricular fibrillation can be delayed or sometimes avoided by gradual cooling. Retrograde warm blood perfusion through the coronary sinus to keep the heart beating has been described. A pulmonary arterial vent can be placed in addition to that in the RSPV; however, if and when there is excessive LV distention, one is forced to arrest the circulation before the desired temperature has been achieved. We describe a technique to prevent LV distention by using an inflated balloon in the LV outflow tract (LVOT), thereby allowing continuation of systemic cooling and coronary perfusion on cardiopulmonary bypass until the goal temperature for DHCA has been achieved.

Magnetic Resonance Imaging Diagnosis of Left Atrial Abscess After Ablation of Atrial Fibrillation

We report a 52-year-old patient with a late presentation of a fistula that occurred after catheter ablation for atrial fibrillation. A secondary left atrial wall abscess was diagnosed by upper endoscopy and cardiac magnetic resonance imaging. Emergency operative repair was successful, with no adverse cardiac or gastrointestinal sequelae.

Emergency Valve Re-Replacement for Embolization of Prosthetic Mitral Valve Disc During Catheterization Procedure

A 47-year-old woman with a mechanical mitral valve underwent a catheter-based atrial fibrillation ablation procedure, which was complicated by the dislodgment and immediate embolization of one of the valve leaflets. Acute severe mitral regurgitation and cardiogenic shock developed, necessitating emergency reoperative mitral valve re-replacement. She subsequently underwent a successful staged retrieval of the embolized leaflet from the abdominal aorta.