Solitary coronary artery nourishing the entire heart.

Coronary artery anomalies are being more frequently diagnosed these days both because increasing numbers of patients are undergoing diagnostic studies and because advanced radiographic imaging methods are now commonly available. An isolated single coronary artery giving rise to the main coronary branches is a rare congenital anomaly. In this report we present a patient with a solitary coronary ostium, with both the left and right coronary artery systems arising from it, and then following their usual courses. This case was diagnosed incidentally during conventional angiography.

The effects of eicosapentaenoic acid on the endothelium of the carotid artery of rabbits on a high-cholesterol diet.

The preventive and therapeutic effects of eicosapentaenoic acid (EPA) on diet-induced hyperlipidemia in rabbits have been investigated. Eighteen New Zealand rabbits were randomly divided into three groups of 6 subjects each; experimental group-I (EG-I) was administered a cholesterol rich diet, experimental group-II (EG-II) was treated with EPA (300 mg/kg/d) following a cholesterol-rich diet and the control group (CG) had a standard diet. Blood samples were collected at day 0 and at the 4th and 12th weeks of EG-II to obtain serum levels of total cholesterol (TC), high density lipid-cholesterol (HDL-C), low density lipid-cholesterol (LDL-C) and triglyceride (TG). From each group tissue samples were collected from the carotid artery for immunohistochemistry and electron microscopy. Our results showed that EPA could significantly lower (p<0.001) serum TC, LDL-C, HDL-C and TG levels with a reduction of 35%; 55%; 44% and 51%, respectively. Scanning and transmission electron microscopy results revealed that endothelial damage was more prominent in EG-I when compared to EG-II. The ruptured endothelial lining and damaged cellular surface was increased in EG-I when compared to EG-II. Ultrastructural observations showed that after EPA treatment, the degeneration and cellular surface damage on the endothelium were also decreased. These biochemical and ultrastructural results suggest that EPA is a potential drug which significantly lowers the serum lipid profile and partially repairs endothelial dysfunction due to hyperlipidemia.

Influence of Tribulus terrestris extract on lipid profile and endothelial structure in developing atherosclerotic lesions in the aorta of rabbits on a high-cholesterol diet.

The aim of this study was to investigate the pleotropic effects of an extract of a traditional herb, Tribulus terrestris (TT), on the lipid profile and vascular endothelium of the abdominal aorta in New Zealand rabbits fed a cholesterol-rich diet. Eighteen rabbits were randomly divided into three groups (n=6 for each). One experimental group (EG-I) was given a cholesterol-rich diet, a second experimental group (EG-II) was treated with TT following a cholesterol-rich diet, and a control group (CG) was fed a standard diet. Blood samples were collected on day 0 and then at weeks 4 and 12 to determine total serum cholesterol (TC), high density lipid-cholesterol (HDL-C), low density lipid-cholesterol (LDL-C) and triglyceride (TG) levels. Tissues were collected from the abdominal aorta for immunohistochemistry and transmission and scanning electron microscopy. In EG-II, the serum lipid profile was significantly lower than that of EG-I at week 12 with a reduction of TC: 65%; LDL-C: 66%; HDL-C: 64%; TG: 55%. Ultrastructural analysis revealed that endothelial damage was more prominent in EG-I compared to EG-II. The ruptured endothelial linings and damaged cellular surfaces increased in EG-I compared to EG-II. Our data indicate that dietary intake of TT can significantly lower serum lipid profiles, decrease endothelial cellular surface damage and rupture and may partially repair the endothelial dysfunction resulting from hyperlipidemia.

Hybrid coronary revascularization in high-risk patients.

From January 2002 through June 2004, 17 patients (2% of all coronary cases) were treated with off-pump coronary artery bypass grafting combined with percutaneous coronary intervention. There were 13 men and 4 women, whose ages ranged from 54 to 78 years (mean, 63.1 +/- 20.9 yr). Preoperative angiography revealed 2-vessel coronary artery disease in 12 patients and 3-vessel disease in the remaining 5 patients. In all patients, extensive lesions (>50%) in the circumflex and right coronary arteries were treated first with a percutaneous intervention, followed by beating-heart coronary artery bypass grafting within 3 hours to treat the remaining obstructed vessels. Coronary angiography was performed 12 months after the operation to evaluate the effectiveness of the procedure. Procedure-related complications did not occur, and there was no in-hospital death. All patients underwent a successful left internal mammary artery-left anterior descending artery anastomosis with the exception of 1 patient, in whom we used a saphenous vein because of previous chest radiotherapy. The postoperative courses were uneventful, and no deterioration of preoperative organ dysfunction was noticed in any patient. There was no cardiac-related death or myocardial infarction. In follow-up angiography, all left internal mammary artery-left anterior descending artery anastomoses were patent. Three patients with restenosis were treated medically, which resulted in substantial reduction of angina. Hybrid coronary revascularization enables complete revascularization and may be an alternative method of treating selected patients who have concomitant disease.

LDH levels and left atrial ultrastructural chances in patients with mitral paraprosthetic regurgitation.

BACKGROUND AND AIM: The aim of this study was to assess the effect of paraprosthetic regurgitation of mitral mechanical valves to myocardial tissue and lactate dehydrogenase (LDH) level. METHODS: We compared 19 patients (study group) who had mitral mechanical valve with severe mitral paravalvular regurgitation with 20 patients (control group) who had native valve with severe rheumatic mitral regurgitation. None of the patients had clinical hemolytic anemia. On transesophageal echocardiographic examination, semiquantative evaluation and spatial distribution of regurgitant jets were noted in both of the groups. Five LDH isoenzymes were studied in two groups. Myocardial tissue specimens were taken from the left atrial wall during reoperation. Grids randomly taken were studied under the transmission electron microscope. RESULTS: Total serum LDH levels of the study group (578 +/- 12 IU/L) were higher than the control group (495 +/- 6.2 IU/L) (p < 0.001). We found LDH1/LDH2 more than 1 in all patients; the ratio was not statistically different in the control group. Electron microscopy revealed the same degree of injury in both groups. Haptoglobin levels were decreased and reticulocyte counts were increased in patients with paraprosthetic valve regurgitation. CONCLUSIONS: Electron microscopic findings support that myocardial injury contributes to increase of total LDH level and high LDH1/LDH2 ratio. But statistically significant elevation in total LDH level in study group and the stable state of LDH1/LDH2 ratio between two groups showed that hemolysis caused by paraprosthetic regurgitation is the most important factor for the increase of total LDH level, so that high LDH level can be used as a reliable parameter for the diagnosis of intravascular hemolysis in paraprosthetic regurgitation.

Dipyridamole myocardial perfusion single photon emission computed tomography in patients with slow coronary flow.

OBJECTIVE: Several studies have indicated that the velocity of contrast dye increases after intravenous dipyridamole infusion in patients with a slow-flow pattern (SFP). In this study we compared the results of coronary arteriography and exercise myocardial perfusion single photon emission computed tomography (SPECT) in patients with SFP. We also investigated the changes in myocardial perfusion in patients with abnormal exercise myocardial perfusion SPECT by using a pharmacological stress test with dipyridamole. DESIGN AND PATIENTS: This study included 60 patients who revealed SFP in their coronary arteriograms. Slow coronary flow diagnoses were made using the frame count method. A single day rest-exercise technetium-99m hexakis-2-methoxy-isobutyl isonitrile (Tc-99m MIBI; Du Pont Pharma SA, Belgium) SPECT was performed in all patients. Patients who had reversible perfusion defect (RPD) on the exercise SPECT were evaluated with dipyridamole myocardial perfusion scintigraphy. RESULTS Patients with SFP revealed both higher frame counts in native coronary arteries and higher mean frame counts. The coronary frame count was 26.4 +/- 3.5 in control patients and 64.40 +/- 16.64 in patients with SFP, respectively (P < 0.001). Exercise perfusion SPECT showed RPD in 17 patients (group 1), but was normal in 43 others (group 2). There were no statistically significant differences between groups 1 and 2 in frame counts. Myocardial perfusion was normalized in all 17 patients of group 1 after dipyridamole infusion. CONCLUSIONS: In patients with SFP perfusion, changes may improve with dipyridamole infusion. This study indicates that this improvement can be shown by dipyridamole SPECT. Furthermore, no correlation was observed between the time needed to fill a native coronary artery and RPD of the myocardium.

Dipyridamole myocardial perfusion tomography in patients with severe aortic stenosis.

UNLABELLED: Patients with aortic stenosis (AS) may have classic angina pectoris. The safety of exercise testing in adults with AS is controversial and, in fact, exercise testing in such patients is considered to be contraindicated especially in severe aortic stenosis (SAS). Furthermore, exercise testing has low specificity in uncovering coronary artery disease (CAD) in patients with AS, because the baseline ECG is frequently abnormal. We wished to assess the safety and diagnostic accuracy of dipyridamole stress myocardial perfusion tomography (DMPT) in the detection of CAD in patients with SAS. METHODS: The study included 30 patients with SAS (mean aortic valve area 0.57 +/- 0.09 cm(2)). All patients underwent dipyridamole myocardial perfusion scintigraphy (SPECT), coronary arteriography and catheterization, as well as Doppler echocardiography. Myocardial perfusion tomography was applied with (99m)Tc hexakis-2-methoxyisobutyl isonitrile (MIBI) by a single day rest-dipyridamole infusion protocol. Hemodynamic, electrocardiographic and clinical responses were compared with those of 50 control patients without AS. RESULTS: Hemodynamic responses during dipyridamole stress tests demonstrated no significant differences between the controls and the AS patients in the following parameters: systolic blood pressure, heart rate, rate-pressure product or incidence of headache, chest pain, dyspnea, flushing and dizziness. A reversible perfusion defect was observed in 10 patients with DMPT. The existence of coronary lesions was determined by coronary arteriography in 8 of 10 patients (sensitivity 100%, specificity 91%). CONCLUSION: The results showed that DMPT is well tolerated, even by patients with SAS and is of high diagnostic value in assessing CAD.