Dani Bitran

Treatment of spontaneous coronary artery dissection: Report of three cases

Spontaneous coronary artery dissection is an extremely rare cause of myocardial infarction. It has been reported mainly in young women during or after pregnancy. The prognosis and treatment of coronary dissection are not clear. We report three cases of spontaneous coronary artery dissection in young women. One of them was pregnant and one was 2 weeks after delivery. The dissection involved the left anterior descending artery (LAD) in two cases and the left main coronary artery in one case. There was no evidence of atherosclerosis on angiography or intracoronary ultrasound in any of the patients. Two of the women were treated by stent implantation with excellent results. This is the first known report of successful coronary stenting of spontaneous coronary artery dissection. The pregnant woman was not a candidate for stent implantation and underwent implantation of the left internal mammary to the LAD without cardiopulmonary bypass. She completed her pregnancy uneventfully.

Exercise hemodynamics of aortic prostheses: comparison between stentless bioprostheses and mechanical valves

BACKGROUND Nonstented bioprostheses have been associated with lower resting gradients than stented bioprostheses or mechanical valves. We compared the hemodynamic performance of nonstented bioprostheses and mechanical valves with normal native aortic valves at rest and exercise. METHODS Dobutamine echocardiography was used to assess gradients and effective orifice area index at rest and exercise in patients with the Toronto stentless porcine valve (TSPV; n = 13; mean implant size 25.7 mm), Medtronic Freestyle (FR; n = 11; mean implant size 23.9 mm), Sorin Bicarbon (SOR; n = 11; mean implant size 24.5 mm), St. Jude Medical (SJM; n = 10; mean implant size 21.3 mm), and normal native aortic valves (NOR; n = 10). RESULTS All groups demonstrated a major rise in cardiac output at maximal dobutamine infusion. At rest and exercise, respectively, mean gradients were 5.48 +/- 1.1 mm Hg and 5.83 +/- 0.9 mm Hg for TSPV, 5.68 +/- 1.2 mm Hg and 7.50 +/- 1.7 mm Hg for FR, 10.29 +/- 1.4 mm Hg and 20.78 +/- 2.7 mm Hg for SJM, 5.26 +/- 0.8 mm Hg and 11.1 +/- 1.8 mm Hg for SOR, and 1.54 +/- 0.4 mm Hg and 2.18 +/- 0.7 mm Hg for NOR. In comparison with normal valves, both stentless groups showed no change in mean gradient at exercise, whereas both mechanical groups showed an increase in gradient at exercise (p < 0.04). CONCLUSIONS Stentless valves behave similarly to normal aortic valves in that there is almost no increase in gradient at exercise. Both mechanical valve groups showed increased gradients at exercise, suggesting that these valves obstruct blood flow. Our data add further evidence that stentless valves are hemodynamically superior to mechanical valves in the aortic position.

Effect of surgical repair of secundum-type atrial septal defect on right atrial, right ventricular, and left ventricular volumes in adults

Surgical repair of atrial septal defect in adults reduces right ventricular and right atrial diameters and volumes, and improves left ventricular filling.

Mitral Valve Repair in Severe Ischemic Cardiomyopathy

Background: Patients with ischemic mitral valve insufficiency (MR) and poor left ventricular (LV) function present a high operative risk. Whether to repair or replace these valves is controversial, while some suggest that heart transplant offers a better solution. We investigated our early and late results in this difficult subset of patients. Methods: Between 1993–1999, 115 patients underwent mitral valve repair (MVR) in our department. Twenty‐one patients had severe LV dysfunction with ejection fraction < 25%. Mean age was 60 years (range 45–81). Nineteen (90%) were in New York Heart Association (NYHA) Class IV, 7 (33%) underwent emergency surgery, 3 (14%) were in cardiogenic shock, and 2 (10%) were taken to the operating room under cardiopulmonary resuscitation. All underwent coronary artery bypass grafting (CABG) in addition to MVR, with a mean number of grafts 2.9 per patient. Results: There were no early operative deaths. The average stay in intensive care was 5.9 days (range 1–52). There were three late deaths (14%). Follow‐up evaluation up to 3 years showed marked improvement in clinical status. Twelve (67%) patients are in NYHA Class I‐II, and three (17%) in Class III. Echocardiography revealed good function of the mitral valve in all, although overall LV function did not change significantly. Conclusion: (1) MVR in patients with severe ischemic cardiomyopathy can be accomplished with excellent results. (2) There is marked symptomatic improvement in these patients, even though LV function did not seem to be improved. (3) Long‐term survival still needs to be defined.

Comparison of exercise hemodynamics among nonstented aortic bioprostheses, mechanical valves, and normal native aortic valves.

Abstract Background: While aortic valve prostheses are known to perform well at rest, few studies have examined them under stress. We compared stress hemodynamics of mechanical valves and nonstented porcine valves in the aortic position to that of normal native aortic valves. Methods: Dobutamine echocardiography was used to assess mean and peak gradients and effective orifice area index (EOAI) at rest and exercise in patients with the Toronto Stentless Porcine Valve (SPV) (n = 13, mean implant size 25.7 mm), Sorin Bicarbon mechanical valve (SOR) (n = 11, mean implant size 24.5 mm), and patients with normal native aortic valves (NOR) (n = 10). Dobutamine infusion was started at 5 µ/kg per minute, and increased by increments of 5 µ/kg per minute until the target heart rate was achieved or until a maximal dose of 40 µ/kg per minute. Results: At rest and exercise, respectively, cardiac output (L/min) was 5.2 and 10.4 for Toronto SPV; 7.4 and 13.5 for SOR; and 4.6 and 11.2 for NOR. Measured EOAI (cm2) was 1.1 ± 0.2 and 1.15 ± 0.2 for TORONTO SPV; 1.60 ± 0.3 and 1.58 ± 0.3 for SOR; and 1.45 ± 0.2 and 1.46 ± 0.2 for NOR. Mean gradients (mmHg) were 5.48 1±.1 and 5.83 ± 0.9 for TORONTO SPV; 5.26 ± 0.8 and 11.3 ± 1.8 for SOR; and 1.54 ± 0.4 and 2.18 ± 0.7 for NOR. Peak gradients (mmHg) were 11.9 ± 2.0 and 21.0 ± 3.7 for TORONTO SPV; 10.79 ± 1.7 and 25.9 ± 3.4 for SOR; and 2.38 ± 0.9 and 6.1 ± 2.3 for NOR. Conclusions: Although the mechanical group (SOR) had larger measured EOAI, the greater increase in gradients with exercise in this group suggests that the TORONTO SPV is less obstructive to flow.

Does coronary endarterectomy increase the risk of coronary bypass

Abstract  Background: With increased incidence of angioplasty and stent implantation, patients referred for coronary bypass (CABG) typically have more advanced and diffuse coronary disease. Thus, more patients may require endarterectomy in order to achieve complete revascularization. We compared our results in patients undergoing CABG with or without coronary endarterectomy. Methods: Between 1993 and 1999, 2372 patients underwent isolated CABG in our department. A retrospective analysis was performed to compare patients requiring coronary endarterectomy of the LAD (group 1, n #88), endarterectomy of arteries other than the LAD (group 2, n #143), to those not requiring endarterectomy (group 3, n # 2071). Patients undergoing CABG without the use of cardiopulmonary bypass were excluded. Group 1 had a higher incidence of proximal LAD stenosis (p #0.001) than group 3, while group 2 had a higher incidence of peripheral vascular disease (p #0.02), preoperative Ml (p # 0.03) and LV dysfunction (p = 0.001). Results: Operative mortality was 10% in group 1 (p < 0.001) and 4% in group 2 (p #IMS) compared to 3% in group 3. Incidence of perioperative Ml was 12% in group 1 (p # 0.001) and 8% in group 2 (p # 0.001) compared to 2% in group 3. Conclusions: Patients requiring endarterectomy of the LAD are at increased risk of operative mortality. This was not true for patients requiring endarterectomy of arteries other than the LAD. In both groups there was an increased risk of perioperative myocardial infarction.

Safety and Tolerability Study of an Intravenously Administered Small Interfering Ribonucleic Acid (siRNA) Post On-Pump Cardiothoracic Surgery in Patients at Risk of Acute Kidney Injury

Introduction Patients undergoing on-pump cardiac surgery are at an increased risk of acute kidney injury. QPI-1002, a small interfering ribonucleic acid, is under clinical development for the prevention of acute kidney injury. The safety, tolerability, and pharmacokinetics of QPI-1002 was evaluated in this first-in-man, Phase 1 study of a small, interfering ribonucleic acid in patients at risk of acute kidney injury after on-pump cardiac surgery. Methods In this phase 1 randomized, placebo-controlled dose-escalation study, a single i.v. dose of QPI-1002 was administered in subjects undergoing on-pump cardiac surgery. Subjects received placebo (n = 4), or QPI-1002 in increasing doses of 0.5 mg/kg (n = 3), 1.5 mg/kg (n = 3), 5 mg/kg (n = 3), and 10 mg/kg (n = 3). Results A total of 16 subjects were enrolled in the study. The average maximum concentration and area under the curve from the time of dosing to the last measurable concentration of QPI-1002 were generally dose proportional, indicating that exposure increased with increasing dose. The average mean residence time (mean residence time to the last measurable concentration) was 10 to 13 minutes in all 4 drug-dosing cohorts. Adverse events occurred at a similar rate in all study groups. Of the total 109 reported adverse events, the events were distributed as 26 in the placebo group and 21, 19, 24, and 19 in the QPI-1002 0.5, 1.5, 5.0, and 10.0 mg/kg groups, respectively. Eight of the 16 subjects experienced at least 1 serious adverse event: 4 (100%) in the placebo group and 4 (33.3%) in the combined QPI-1002 cohorts. Discussion QPI-1002 was rapidly eliminated from plasma. QPI-1002 was safe and well tolerated across all dose groups. Overall, no dose-limiting toxicities or safety signals were observed in the study. Further development of QPI-1002 for prophylaxis of acute kidney injury is warranted.

No Symptomatic Intracerebral Hemorrhage after Cardiac Surgery: A 14-Year Retrospective Study

Background: In the presence of new neurological findings occurring after cardiac surgery, the clinical question is whether to exclude symptomatic intracerebral hemorrhage (ICH), particularly in the context of routine postoperative anticoagulation treatment. Methods: This is a retrospective 14-year study including 5,275 patients who underwent cardiovascular surgery. The control cohort included all patients with acute cerebrovascular accidents hospitalized in 2 general hospitals in Jerusalem during a 2-month period in 2007 (part of a national survey). Results: After cardiac surgery, 78 patients developed ischemic strokes, mostly of large-vessel etiology. These ischemic strokes occurred more often in patients who underwent combined operations (22/647 = 3.4% vs. 45/3,489 = 1.3%; p = 0.0004). ICH was found in 6% of all acute cerebrovascular accidents in the general survey, but was absent after cardiac surgery (5 vs. 0; p = 0.02). Conclusions:Despite hypertension as a main risk factor and the administration of postoperative anticoagulation, we found that symptomatic ICH did not occur after cardiac surgery.