Mikhail Vaynblat

Simultaneous angiotensin converting enzyme inhibition moderates ventricular dysfunction caused by doxorubicin

The purpose of this study was to determine that the administration of an angiotensin converting enzyme (ACE) inhibitor enalapril would confer protection against doxorubicin‐induced experimental heart failure, and attenuate the development of left ventricular dysfunction.

Expedient pulmonary embolectomy for acute pulmonary embolism: improved outcomes.

Indications regarding surgical pulmonary embolectomy for treatment of submassive/massive acute pulmonary embolism remain controversial. An institutional experience with pulmonary embolectomy for acute pulmonary embolism (APE) was reviewed. A retrospective analysis of all patients undergoing pulmonary embolectomy for APE from September 2004 to January 2007 was conducted. Demographic data, clinical presentation and outcomes were analyzed. Fifteen patients underwent surgery for APE over a period of 27 months [average age 59.6 (range 35-89) years, (seven male, eight female)]. Six (40%) patients were admitted with known APE and nine patients exhibited post admission APE (seven - after surgical procedures, two - after cerebrovascular accident). Clinical presentation included dyspnea (86.67%), hemodynamic instability requiring continuous vasopressor support (40%), echocardiographic evidence of right ventricular dilatation (80%). Ten patients undergoing early/expedient embolectomy all survived while delayed surgery in the other five patients (>24 h) was associated with 60% mortality. Expanding indications for early surgical pulmonary embolectomy has stemmed from reliable echocardiographic identification of right ventricular compromise and recognition of these findings as harbingers of subsequent hemodynamic embarrassment. Our series underscores the benefit of early consideration and performance of pulmonary embolectomy in these critically ill patients.

Use of Argatroban for anticoagulation during cardiopulmonary bypass in a patient with heparin allergy.

The use of Argatroban for treatment of heparin-induced thrombocytopenia (HIT) and for percutaneous coronary intervention in patients with HIT is well described and FDA approved. The use of Argatroban for cardiopulmonary bypass remains off label and the subject of a few case reports. We report the case of a patient with a heparin allergy requiring cardiopulmonary bypass (CPB) for mitral valve replacement. Argatroban was successfully used as anticoagulation for CPB.

Open heart surgery in patients 85 years and older.

Abstract  Background: There has been an increase in the number of elderly patients considered for cardiac surgery. Several reports have documented acceptable morbidity and mortality in patients 80 years and older. The results from surgical patients 85 years and older were analyzed. Methods: The records of 89 consecutive patients 85 years and older having cardiac operations between June 1993 and May 1999 were retrospectively reviewed. For purposes of statistical analysis follow‐up was considered as a minimum of one office visit to the surgeon, cardiologist, or internist at least 1 month postoperatively. Results: Eighty‐seven patients underwent coronary artery grafting and two patients had mitral valve replacement. Follow‐up was 100% complete. The operative mortality rate was 12.3%; probability of in‐hospital death was 8.2%; risk‐adjusted mortality rate was 3.2%. The complication rate was 31.5%. The actuarial 1‐, 3‐, and 5‐year survivals were as follows: 75%, 67%, and 40%. Multivariate predictors of 30‐day mortality were preoperative EF, less than 30% (p = 0.029) and postoperative renal failure (p = 0.0039). Conclusions: Cardiac surgery can be performed in patients 85 years and older with good results. There is an associated prolonged hospital stay for elderly patients. Consistent successful outcomes can be expected in this patient population with selective criteria identifying risk factors. (J Card Surg 2004;19:7‐11)

Relationship Between Upper Airway Obstruction and Gastroesophageal Reflux in a Dog Model

The association between gastroesophageal reflux (GER) and upper airway obstruction in children is recognized but not well understood. Our objective was to determine if the creation of a model of upper airway obstruction in dogs would cause GER and to determine if the GER is related to intrathoracic pressure changes. Five dogs underwent evaluation with esophageal manometry and pH probe at baseline and 1 week after creation of an upper airway obstruction. Airway obstruction was created by placement of a fenestrated cuffed tracheostomy tube, which was then capped and the cuff was inflated, requiring the animals to breathe via the fenestrations. The negative inspiratory pressure (Pes) (± SD) increased from 11.8 ± 4.8 cm H2O at baseline to 17.6 ± 4.9 cm H2O 1 week after creation of an airway obstruction (p =. 029). None of the dogs had GER at baseline with a reflux index (RI) value of 0.0; however, 1 week after creation of airway obstruction, three out of five dogs had GER, with a mean RI value of 21.2 ± 21.2. There was a significant (p =. 023) correlation (r =. 928) of the changes in Pes and RI values following airway obstruction.Upper airway obstruction (UAO) does cause GER in this canine model. Severity of GER is significantly correlated with Pes changes.

Cardiac Valve Papillary Fibroelastoma: Surgical Excision for Revealed or Potential Embolization

Abstract  Cardiac papillary fibroelastomas (CPF) are benign endocardial papillomas commonly formed from valve endothelium. The majority of tumors are found on the left side of the heart, with only a few case reports of pulmonary valve fibroelastomas. We report here a case of pulmonary valve papillary fibroelastoma that was successfully managed with simple excision of the mass.

Telemetrically monitored arrhythmogenic effects of doxorubicin in a dog model of heart failure

A model of chronic heart failure has been induced in dogs by repeated intracoronary infusion of doxorubicin, which is an antineoplastic medication that has dose-limiting cardiotoxic side effects. Although many of the dogs receiving doxorubicin develop typical signs of dilated cardiomypathy over 4-6 weeks, some of them suddenly die before completing the four weekly infusions of the drug. The present study was undertaken to determine whether such sudden death may be caused by the development of fatal arrhythmias during doxorubicin treatment. This was assessed by telemetrically monitoring the EKG of seven dogs, which received intracoronary infusion of 1 mg/kg doxorubicin given in four divided weekly doses. The recordings were obtained for 8-10 h on alternate days up to 4 weeks. Echo-cardiographic recordings were obtained once a week. The acute effects with each infusion of doxorubicin included a significant increase in heart rate, and no significant change in QRS complex. The cumulative prolonged effects of doxorubicin included slight reduction in QRS amplitude and duration, and marked arrhythmic changes. Four out of seven dogs showed a spectrum of arrhythmic events such as single or groups of premature ventricular complexes (PVCs), bigeminy, ventricular tachycardia (VTAC), ventricular fibrillations (VFIB), and asystole. All dogs did not show each of the events listed above and the same dog did not show all the events all the time. One of these four dogs developed VFIB for 25 min and then asystole leading to sudden death. These studies conclusively showed that fatal arrhythmias develop in some of the dogs receiving doxorubicin treatment accounting for the sporadic incidence of sudden death. Prophylactic treatment with antiarrhythmic agents may prevent such adverse events.

Circadian Rhythm has no Effect on Mortality in Coronary Artery Bypass Surgery

Abstract  Background: The circadian variation that affects atherosclerosis has not been studied in the surgical patient. The circadian variation in mortality dependent on the time of surgery was examined in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: A 4‐year retrospective review of all CABG patients (n = 3140) from 1999 to 2002 was undertaken. The patients were divided into elective, urgent, and emergency cases. The cases were subdivided according to the start time of the operation as morning (7 AM to 2 PM = AM), afternoon (2 PM to 8 PM = AF), and night (8 PM to 7 AM = NT). The outcome was mortality within 30 days and compared for three different time frames: (1) AM versus AF (2) AM versus NT (3) AF versus NT for each prioritized group. Risk factors and number of anastamoses were compared for each group. Sigma Statistical package and Z‐test for two group comparison were used for analysis. t‐Test was used to compare age and ejection fraction. Results: No statistically significant difference in mortality was observed for the elective and urgent groups for each of the time periods compared. The emergency cases had significantly increased deaths in the AM and NT compared to the AF (p < 0.01 and p < 0.05, respectively). There was no statistically significant difference with respect to age, gender, number of anastamoses performed, ejection fraction, and preoperative risk factors between groups. Conclusions: The mortality for nonemergent CABG is independent of the timing of surgery. Circadian variation does not influence the outcome in cardiac surgical patients.

Lipid-laden macrophage index in healthy canines.

Background  The quantity of lipids in alveolar macrophages is used clinically as an indicator of aspiration, which is associated with increased lung inflammation. This is determined in the macrophages obtained from bronchoalveolar lavage (BAL) and is expressed as lipid‐laden macrophage index (LLMI). Although there is ample data on LLMI in human subjects, there is no published data pertaining to the baseline measures of the LLMI in canines, which are extensively used for experimental studies on gastroesophageal reflex (GER) and airway diseases. Primary aim of the present study was to collect data pertaining to the cytology and LLMI in BAL fluids obtained from healthy dogs.

The effect of surgically created gastroesophageal reflux on intrapleural pressures in dogs

The causal relationship between gastroesophageal reflux (GER) and respiratory disorders is not well understood. Previous experimental studies that investigated this relationship were performed in anesthetized animals and used artificial acidification of esophagus for simulation of GER. In this study, we investigated the impact of GER on intrapleural pressures (IPP) in conscious, unanesthetized dogs. After the induction of appropriate anesthesia, 5 purpose-bred mongrel dogs underwent reflux-creating surgery (partial cardiomyectomy). The presence of GER was confirmed by determining the reflux index (RI) and the duration of longest reflux episode (DLRE) after 24-h intraesophageal pH-metry. IP was monitored before and after cardiomyectomy using a subcutaneously placed telemetric implant with its pressure-sensor catheter tip inserted into the pleural space. Partial cardiomyectomy resulted in a significant increase in RI from a preoperative mean value of 0.38 +/- 0.21 to 7.52 +/- 2.56%, and DLRE from 1.22 +/- 1.12 to 36.80 +/- 12.71 min, as recorded by the proximal sensor of the pH probe. A similar trend was observed at the distal sensor. After cardiomyectomy, the negative inspiratory IPP significantly increased from 17.2 +/- 7.9 to 28.4 +/- 9.7 mm Hg. A similar effect was observed in the negative expiratory IPP. The negative inspiratory IPP had a significant correlation with both RI (R = 0.932) and DLRE (R = 0.899). Cardiomyectomy causes GER, the severity of which correlates with negative inspiratory IPP in a dog model. The suggested model allows for the investigation of the pathologic association of GER with respiratory disorders in conscious animals.