Human Induced Pluripotent Stem Cell-Derived Cardiomyocyte Patch in Rats With Heart Failure.

BACKGROUND: To treat chronic heart failure (CHF), we developed a robust, easy to handle bioabsorbable tissue-engineered patch embedded with human neonatal fibroblasts and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). This patch was implanted on the epicardial surface of the heart covering the previously infarcted tissue. METHODS: Sprague-Dawley rats (6-8 weeks old) underwent sham surgery (n = 12) or left coronary artery ligation (n = 45). CHF rats were randomized 3 weeks after ligation to CHF control with sham thoracotomy (n = 21), or a fibroblasts/hiPSC-CMs patch (n = 24) was implanted. All sham surgery rats also underwent a sham thoracotomy. At 3 weeks after randomization, hemodynamics, echocardiography, electrophysiologic, and cell survival studies were performed. RESULTS: Patch-treated rats had decreased (P < .05) left ventricular-end diastolic pressure and the time constant of left ventricular relaxation (Tau), increased anterior wall thickness in diastole, and improved echocardiography-derived indices of diastolic function (E/e' [ratio of early peak flow velocity to early peak LV velocity] and e'/a' [ratio of early to late peak left ventricular velocity]). All rats remained in normal sinus rhythm, with no dysrhythmias. Rats treated with the patch showed improved electrical activity. Transplanted hiPSC-CMs were present at 7 days but not detected at 21 days after implantation. The patch increased (P < .05) gene expression of vascular endothelial growth factor, angiopoietin 1, gap junction α-1 protein (connexin 43), ß-myosin heavy 7, and insulin growth factor-1 expression in the infarcted heart. CONCLUSIONS: Epicardial implantation of a fibroblasts/hiPSC-CMs patch electrically enhanced conduction, lowered left ventricular end-diastolic pressure, and improved diastolic function in rats with CHF. These changes were associated with increases in cytokine expression.

Surgical treatment for heart failure: cell-based therapy with engineered tissue.

This review will outline cell-based therapy for heart failure focusing on tissue engineering to deliver cells to the damaged heart. We will present an overview of the central approaches focusing on pluripotent stem cell-derived cells, mechanisms of action, autologous vs. allogeneic cell approaches, immunologic modulation, and safety considerations. We will outline the progress that has been made to-date and define the areas that still need to be investigated in order to advance the field.

Factors in the Selection and Management of Chest Tubes After Pulmonary Lobectomy: Results of a National Survey of Thoracic Surgeons.

BACKGROUND: This study determined patterns of chest tube (CT) selection and management after open lobectomy and minimally invasive lobectomy by thoracic surgeons. METHODS: Surveys were sent electronically to 5,175 thoracic surgeons, and 475 were completed. Responses, blinded so individuals could not be identified, were analyzed and compared according to surgeon characteristics (academic/private practice, years in practice, lobectomy volume, and geographic region). All indicated differences were statistically significant (p < 0.05 by χ(2) tests). RESULTS: CT selection: Most surgeons prefer rigid tubes, and the size most commonly used was 28F. Most place 2 CTs after open lobectomy and 1 CT after minimally invasive lobectomy. Academic surgeons are more likely than private surgeons to use 1 tube after open lobectomy, but both prefer 1 tube after minimally invasive lobectomy. Younger surgeons and high-volume surgeons are more likely to use 1 CT than senior surgeons and low-volume surgeons after both open lobectomy and minimally invasive lobectomy. CT management: Academic and younger surgeons remove the CT sooner after open lobectomy. Younger and high-volume surgeons remove the CT with greater drainage amounts. All groups remove CTs sooner after minimally invasive lobectomy than after open lobectomy. Approximately half of surgeons get a daily chest roentgenogram. Younger and low-volume surgeons are most likely to discharge patients with Heimlich valves, although overall use was in less than 5% (49 of 475) of respondents. Most surgeons believe clinical experience rather than training or the literature determined their CT strategy. CONCLUSIONS: This survey determined the difference in CT management among various groups of surgeons. Clinical experience was the most important factor in determining their CT strategy.