The Journal of Tehran University Heart Center
Volume:7 Issue: 3, Jul 2012

Repair of the mitral valve is the treatment of choice for mitral valve regurgitation when the anatomy is favorable. It is well known that mitral valve repair enjoys better clinical and functional results than any other type of valve substitute. This fact is beyond doubt regardless of the etiology of the valve lesion and is of particular importance in degenerative diseases.This review analyzes the most important advances in the knowledge of the anatomy, pathophysiology, and chordal function of the mitral valve as well as the different alternatives in the surgical repair and clinical results of the most prevalent diseases of the mitral valve. An attempt has been made to organize the acquired information available in a practical way.

The optimal strategy in percutaneous coronary intervention (PCI) for coronary artery bifurcation lesions has yet to be agreed upon. We compared a strategy for stenting the main vessel to provide a complete perfusion flow in the side branch, namely thrombolysis in myocardial infarction (TIMI) - III, with a strategy for intervention in both the main vessel and the side branch (MV + SB). This retrospective study utilized data on 258 consecutive patients with bifurcation lesions scheduled for PCI at Tehran Heart Center between March 2003 and March 2008. The patients were followed up for 12 months, and the primary end point was a major adverse cardiac event (MACE), i.e. cardiac death, myocardial infarction, target-vessel revascularization, and target-lesion revascularization during the 12-month follow-up period. A total of 52.7% of the patients underwent PCI on the main vessel of the bifurcation lesions (MV group) and 47.3% with a similar lesion type received a percutaneous intervention on both the main vessel and the side branch (MV + SB group). The total rate of MACE during the follow-up was 4.3% (11 patients); the rate was not significantly different between the MV and MV + SB groups (3.7% vs. 4.9%, respectively; p value = 0.622). There was no association between MACE in performing a simple or complex interventional strategy to treat coronary bifurcation lesions when drawing the TIMI- III flow as a goal in a simple technique.

Sickle-cell disease (SCD) is an inherited hemoglobin childhood disorder, frequently complicated by pulmonary hypertension and cardiac involvement. Cardiovascular events and complications are the leading cause of mortality and morbidity in patients with SCD. Tissue Doppler imaging and the myocardial performance index (Tei index), are simple indices for the assessment of the cardiac function. The purpose of this study was to assess the left ventricular function in children with SCD. Sixty-four patients with SCD (mean age = 11.7 ± 5.5 years) were compared with 50 age‑matched healthy controls (mean age = 11.2 ± 5.20 years). Myocardial wall motion velocities at the lateral mitral annulus and the junction between the medial mitral annulus and the interventricular septum were assessed during systole (Sa), early diastole (Ea), and late diastole (Aa) through a four-chamber view using pulsed Doppler echocardiography. The ejection fraction and shortening fraction were estimated. The Tei index was estimated via tissue Doppler echocardiography. The results showed that Ea and Aa velocity in the mitral annulus and interventricular septum had no difference between the patients and controls (p value > 0.05), and nor was there any difference between the two groups as regards the Tei index, Ea/Aa, ejection fraction, and shortening fraction (p value > 0.05). Sam wave velocity, however, had a significant difference between the two groups (p value < 0.038). The Tei index is a sensitive indicator for the cardiac function in chronic diseases and the right ventricular function in some disorders such as SCD.

The Adult Cardiac Surgery Databank (ACSD) of Tehran Heart Center was established in 2002 with a view to providing clinical prediction rules for outcomes of cardiac procedures, developing risk score systems, and devising clinical guidelines. This is a general analysis of the collected data. All the patients referred to Tehran Heart Center for any kind of heart surgery between 2002 and 2008 were included, and their demographic, medical, clinical, operative, and postoperative data were gathered. This report presents general information as well as in-hospital mortality rates regarding all the cardiac procedures performed in the above time period. There were 24959 procedures performed: 19663 (78.8%) isolated coronary artery bypass grafting surgeries (CABGs); 1492 (6.0%) isolated valve surgeries; 1437 (5.8%) CABGs concomitant with other procedures; 832 (3.3%) CABGs combined with valve surgeries; 722 (2.9%) valve surgeries concomitant with other procedures; 545 (2.2%) surgeries other than CABG or valve surgery; and 267 (1.1%) CABGs concomitant with valve and other types of surgery. The overall mortality was 205 (1.04%), with the lowest mortality rate (0.47%) in the isolated CABGs and the highest (4.49%) in the CABGs concomitant with valve surgeries and other types of surgery. Meanwhile, the overall mortality rate was higher in the female patients than in the males (1.90% vs. 0.74%, respectively). Isolated CABG was the most prevalent procedure at our center with the lowest mortality rate. However, the overall mortality was more prevalent in our female patients. This database can serve as a platform for the participation of the other countries in the region in the creation of a regional ACSD.

Pregnant patients with mechanical heart valves require anticoagulation. The risk of bleeding and embryopathy associated with oral anticoagulants must be weighed against the risk of valve thrombosis. In this prospective study, undertaken between 1999 and 2009, 53 pregnancies (47 women with mechanical mitral valves; 29.8 ± 4.8 years old) were studied. Patients were divided into two groups: group I (n = 43) received Warfarin throughout the pregnancy, while group II (n = 10) received Heparin in the first trimester and then Warfarin until the 36th week. Thirty-two (60.4%) pregnancies resulted in live births, whereas 18 (34%) abortions, 2 (3.8%) stillbirths, and one (1.9%) maternal death occurred. In group I, there were 26 (60.5%) live births, one (2.3%) stillbirth, and 15 (34.9%) abortions. In group II, there were 6 (60%) live births, one (10%) stillbirth, and 3 (30%) abortions. There were no significant differences between the two groups in terms of fetal outcome. Thirty-nine (90.7%) of the pregnancies in group I and 50% of those in group II (p value = 0.001) were without complications. There were no congenital malformations in the two groups. Fetal outcome was almost the same between the Warfarin and Heparin regimens. In maternal outcome, the Warfarin regimen is safer than Heparin.

Extubation is associated with the risk of complications such as accumulated secretion above the endotracheal tube cuff, eventual atelectasia following a reduction in pulmonary volumes because of a lack of physiological positive end expiratory pressure, and intra-tracheal suction. In order to reduce these complications, and, based on basic physiological principles, a new practical extubation method is presented in this article. The study was designed as a six-month prospective cross-sectional clinical trial. Two hundred fifty-seven patients undergoing coronary artery bypass grafting (CABG) were divided into two groups based on their scheduled surgery time. The first group underwent the conventional extubation method, while the other group was extubated according to a new described method. Arterial blood gas (ABG) analysis results before and after extubation were compared between the two groups to find the effect of the extubation method on the ABG parameters and the oxygenation profile. In all time intervals, the partial pressure of oxygen in arterial blood / fraction of inspired oxygen (PaO2 / FiO2) ratio in the new method group patients was improved compared to that in the conventional method; some differences, like PaO2 / FiO2 four hours after extubation, were statistically significant, however (p value = 0.0063). The new extubation method improved some respiratory parameters and thus attenuated oxygenation complications and amplified oxygenation after extubation.

In this study, we used a new computerized analytical method for the measurement of the endothelial function in sequential ultrasound images and compared it with histological studies, using the abdominal aorta in normal and atherosclerotic rabbits. Six rabbits received a standard rabbit chow as the normal group and the other 6 rabbits were fed a high cholesterol diet for four weeks as the atherosclerotic group. B-mode images of the abdominal aorta with 46 frames per second were saved over three cardiac cycles at baseline and during acetylcholine or nitroglycerin drug infusion in the normal and atherosclerotic rabbits. In order to evaluate endothelial-dependent relaxation, acetylcholine-mediated dilation (AMD) was measured during the infusion of acetylcholine at a rate of 0.5 µg/kg/min and endothelial-independent relaxation was evaluated by measuring nitroglycerine-mediated dilation (NMD) during the infusion of nitroglycerin at a rate of 5 µg/kg/min. In addition, the ultrasonic evaluation was confirmed by histopathological evaluation of the abdominal aorta. Significant differences in AMD were detected between the normal and the four-week cholesterol-fed rabbits (p value < 0.05), whereas there were no significant differences in NMD between the two groups (p value > 0.05). No microscopic intimal lesions were seen in the normal rabbits, but intimal thickening was observed in the histological studies in the four-week cholesterol-fed rabbits. Additionally, the total cholesterol, triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were remarkably increased in the sera of the four-week cholesterol-fed rabbits (p value < 0.05). A new automatic method can help accurately evaluate the endothelial function in normal and hypercholesterolemic rabbits.

Stress-induced cardiomyopathy or Takotsubo cardiomyopathy is a recently increasing diagnosed disease manifested by transient apical or mid left ventricular dilation and dysfunction. This sign is similar to acute myocardial infarction but without significant coronary artery stenosis. There are important and essential differences between Takotsubo cardiomyopathy and acute myocardial infarction in terms of management, necessitating a good understanding of the pathophysiology, diagnosis, and treatment of the former.We report a case of Takotsubo cardiomyopathy which presented with dizziness and near syncope after an intense emotional stress. Electrocardiogram showed ST-T changes in V1-V3 and echocardiography revealed severe left ventricular systolic dysfunction with marked regional wall motion abnormalities. Coronary angiography demonstrated minimal coronary artery disease. The patient was treated with beta -blockers, angiotensin-converting enzyme inhibitors, Aspirin, Clopidogrel, and diuretics. At the follow-up visit, all the symptoms had disappeared and control echocardiography showed significant improvement in the left ventricular systolic function with a normal ejection fraction and normal wall motion.

Isolated dissection of the superior mesenteric artery is a rare occurrence with a hitherto unknown exact etiology. Patients may present with abdominal symptoms or hemodynamic instability.We herein present a case of spontaneous isolated superior mesenteric artery dissection in a 48-year-old man, who was admitted with epigastric pain. Due to an undiagnosed paced rhythm on the electrocardiogram, he was given fibrinolysis treatment for acute myocardial infarction. On further evaluation, angiography revealed that the cause of pain was the dissection of the superior mesenteric artery. The patient’s symptoms were diminished with conservative management, obviating the need for the angioplasty of the superior mesenteric artery.

The term “stunned myocardium” refers to abnormalities in the myocardial function following reperfusion and is common in on-pump coronary artery bypass grafting (CABG) and is exceedingly rare in off- pump CABG. A 53-year-old man presented with unstable angina due to the severe stenosis of the left anterior descending coronary artery (LAD) and the obtuse marginal. Laboratory findings and Chest X-ray revealed nothing abnormal. The intraoperative course was uneventful. The patient left the operating room without any inotropic support. Six hours later, however, he developed low cardiac output. At exploration, cardiac tamponade was excluded and flowmetry showed that the graft had adequate function. Cardiac enzymes were normal. High-dose adrenalin and Dobutamine were administrated and an intra-aortic balloon pump was used. After hemodynamic stabilization, the patient left the Intensive Care Unit without an intra-aortic balloon pump and inotropic support. On the fifth postoperative day, coronary angiography showed patent grafts and correct anastomotic sites. On the seventh postoperative day, the akinetic lateral wall of the left ventricle changed to dyskinesia. Finally after hospital discharge on the thirtieth postoperative day, an echocardiogram showed normal left ventricular function without regional wall motion abnormalities.