Comparison of fibrinolytic versus surgical therapy in the treatment of obstructive prosthetic valve thrombosis: a single-center experience.

OBJECTIVE: Prosthetic heart valve thrombosis (PVT) is a rare but severe cardiac condition. There are only a few data regarding comparison of the fibrinolytic and surgical approaches for the treatment of PVT. In this study, we compared the results of fibrinolytic therapy versus surgery in patients who presented to our institution with a diagnosis of obstructive-type PVT. METHODS: From January 2001 to August 2008 in our institution, 33 patients who met clinical and echocardiographic criteria for obstructive-type PVT were included in the study. Fifteen of these patients underwent fibrinolytic treatment with streptokinase, which consisted of an initial bolus of 250,000 U followed by 100,000 U/h. Eighteen patients were treated with surgery. RESULTS: The 2 groups had similar baseline characteristics, including New York Heart Association functional status, types and positions of prosthetic valves, international normalized ratio values, and presentation symptoms. Full hemodynamic success was achieved in 12 patients who underwent fibrinolytic therapy and in 15 patients in the surgery group. The mean (±SD) streptokinase infusion time was 17.8 ± 11.1 hours. Two major hemorrhages and 2 cases of systemic embolism were observed in the fibrinolytic group. The 2 groups did not differ with respect to mortality rate (P = .79). The duration of hospitalization was longer in the fibrinolytic group than in the surgery group (10.7 ± 6.6 days versus 6.9 ± 6.7 days, P = .045). CONCLUSIONS: Although fibrinolytic therapy is generally recommended for the treatment of PVT for specific patient groups, our results suggest that it may be as efficacious and safe as surgery, depending on patient selection.

Coronary lesion type, location, and characteristics of acute ST elevation myocardial infarction in young adults under 35 years of age.

OBJECTIVE: In the present study, we attempted to analyze the coronary artery lesion characteristics of acute ST elevation myocardial infarction (STEMI) in young patients (aged less than 35 years). METHODS: We retrospectively surveyed 25 038 coronary angiography procedures, which were carried out at The Baskent University Adana Hospital from 1998 to present, to discover acute STEMI in young patients. We studied clinical risk factors and angiographic characteristics in 42 consecutive patients who underwent primary coronary angiography for acute STEMI. Control group (n=42) had no history of coronary artery disease and had angiographically proven normal coronary arteries. All patients were under 35 years of age. Angiographic features for STEMI group were collected and both groups were compared for coronary risk factors. RESULTS: Male sex was more prevalent in acute STEMI group when compared with control participants (83 vs. 59%, respectively; P=0.01). A significant difference was found in cigarette smoking (62 vs. 36%, respectively; P=0.007) and family history (33 vs. 16%, respectively; P=0.03) between the two groups. No statistical significance was observed between the groups in terms of hypertension, diabetes mellitus, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels. Mean high-density lipoprotein cholesterol level was 33+/-8 mg/dl in STEMI group and 39+/-12 mg/dl in control participants (P=0.02). Young patients with acute STEMI showed a preponderance of single-vessel disease (69%) and acute anterior STEMI (60%) owing to occluded left anterior descending artery (P<0.001). CONCLUSION: We observed risk factors such as family history, smoking, and low high-density lipoprotein cholesterol levels in young adults. Acute anterior STEMI owing to occluded left anterior descending artery was more frequent. Coronary atherosclerosis was characterized by higher presence of type B and proximal lesions. The handling selection was percutaneous coronary intervention in more than half of the patients.

An unusual cause of mismanagement in an acute myocardial infarction case: pseudothrombocytopenia.

Thrombocytopenia determined by an automated counter may represent a benign, incidental finding in an asymptomatic patient or a potentially life-threatening disorder. Even if the low platelet count actually is a benign condition itself, in some conditions, any delay resulting from this condition consequently may be seriously hazardous. Low platelet count may alter the decision of heparin administration, which is an essential part of management during acute coronary syndromes. EDTA-dependent pseudothrombocytopenia (PTCP) is reported to have a prevalence of 0.1% in a general hospital; however, it is also reported that around 15% of the patients referred for a specialized center for isolated thrombocytopenia are actually cases of PTCP. In this report, we describe a patient with PTCP who could not receive reperfusion therapy during acute myocardial infarction because of the low platelet counts reported by an automated counter.

Intima-media thickness in patients with rheumatic mitral stenosis.

The aim of the study was to determine carotid artery intima-media thickness (IMT) in patients with rheumatic mitral stenosis (RMS). Between January 2001 and December 2003, 112 consecutive patients who had been diagnosed with RMS were screened. Patients with known cerebrovascular disease, coronary artery disease, diabetes, hypertension, left ventricular hypertrophy, hyperlipidemia, abnormal laboratory results, smoking, or age over 50 years were excluded. Forty-eight patients (43 women, 5 men, mean age 39.7 +/-8.3 years) with RMS without risk factors were enrolled in the study. Age- and sex-matched healthy individuals (n = 48; 43 women, 5 men, mean age 39.6 +/-8.6 years) with normal echocardiographic findings constituted the control group. Carotid IMT was determined by using a high-resolution ultrasound system equipped with a 7-MHz imaging probe (Acuson 128 XP CI) with a computer measurement software. The mean common carotid artery IMT thicknesses both in the right (0.604 +/-0.112 mm vs 0.521 +/-0.072 mm) and in the left side (0.581 +/-0.097 mm vs 0.516 +/-0.065 mm) were significantly higher in patients with RMS than in the control group (p < 0.001). Backward stepwise logistic regression analysis identified RMS as independent predictors of increased IMT (OR, 17.25 (CI, 3.99 to 76.28), p <0.001). The present study demonstrated that RMS is associated with increased IMT. The findings indicate that in patients with RMS not only valvular but also systemic endothelium is damaged.

Effect of coronary artery bypass grafting and aneurysmectomy on QT dispersion in moderate or severe left ventricular dysfunction.

BACKGROUND: The aim of the study was to evaluate the effect that coronary artery bypass grafting (CABG) and aneurysmectomy in the same session have on QT dispersion (QTd) in moderate or severe left ventricular dysfunction. METHODS: Forty-four patients underwent QT interval analyses before and 1 month after aneurysmectomy and CABG. QT interval and QTd were corrected for heart rate using the square root formula of Bazett (QTCB), the cubic root formula of Fridericia (QTCF), and the linear formula of Sagie et al (QT CS ). RESULTS: The mean pre- and postsurgery QTd results were 65.29 +/- 29.25 and 51.76 +/- 18.49 milliseconds, respectively; the corresponding findings for QT CF were 68.06 +/- 31.26 and 55.16 +/- 24.56 milliseconds; and the corresponding findings for QT CS were 66.53 +/- 32.22 and 51.10 +/- 18.29 milliseconds. With these 3 methods, the postoperative findings were significantly lower than the preoperative findings ( P < .05 for all). In contrast, the opposite was true with the QT CB method (preoperative 71.1 +/- 65.80 vs postoperative 76.43 +/- 7.96 milliseconds, P < .05). CONCLUSION: The study showed that based on the methods of Fridericia (QT CF ) and Sagie et al (QT CS ), QT intervals are significantly decreased after CABG and aneurysmectomy.

On-pump/beating-heart myocardial protection for isolated or combined coronary artery bypass grafting in patients with severe left ventricle dysfunction: assessment of myocardial function and clinical outcome.

BACKGROUND: Myocardial protection in coronary artery bypass grafting (CABG) with severe left ventricular (LV) dysfunction is still a surgical dilemma. Preoperative myocardial infarction (MI) and postoperative low output syndrome are serious complications in cases of inadequate protection of the heart, which has limited myocardial reserve. The aim of this study was to evaluate myocardial function and clinical outcome after on-pump/beating-heart CABG in patients with severe LV dysfunction. METHODS: Between March 2001 and March 2004, clinical, operative, and postoperative data were prospectively collected from patients with LV ejection fraction (EF) < 30% who underwent on-pump/beating-heart CABG and associated procedures. RESULTS: There were 46 patients and the mean patient age was 58.38 +/- 9.23. The mean EF was 25.6 +/- 2.8%. Operating time was 275 +/- 63 minutes. The frequency of distal anastomosis was 3.06 +/- 1.04. Twenty-four patients required aneurysmectomy in addition to CABG, and 2 of the 24 required mitral repairs. Inotropic support was required in 14 patients (30%) and 5 of them (10.9%) also required IABP. The LV EF improved significantly after the operation when compared to preoperative measurements (25.6 +/- 2.8 versus 33.64 +/- 4.69, P < .05). Hospital mortality rate was 4.3% (2 of the 46 patients). No mortality was observed at a mean followup of 16 months after discharge from the hospital. CONCLUSIONS: On-pump/beating-heart CABG technique is effective in protecting myocardial functions in patients with severe LV dysfunction. The main advantage of the on-pump/beating-heart technique is the ability it provides one to perform complete revascularization, and intracavitary procedures with low morbidity and mortality even in impaired LV function.

Findings of ambulatory blood pressure monitoring and heart rate variability in patients with Behcet's disease.

Although we found lack of a decrease in nocturnal blood pressure, impaired heart rate variability, and diastolic dysfunction in patients with Behcet's disease, we could not demonstrate whether or not this finding has a prognostic value in patients with this disease.

Vascular endothelial function and plasma homocysteine levels in Behcet's disease.

The purpose of the present study was to test endothelial function and to determine if plasma homocysteine levels are associated with endothelial injury in patients with Behcet's disease (BD). Flow-mediated dilation in patients with BD was smaller than that of control subjects (p = 0.001), and mean plasma homocysteine levels in patients with BD were significantly higher (p = 0.0001). On regression analysis, only mean plasma homocysteine concentration was independently related to flow-mediated dilation (F = 5.7, p = 0.001).

[Are there effects due to the existence of coronary collateral circulation on left ventricular function in patients with coronary artery disease?]. / Koroner arter hastaliginda kollateral dolasim varliginin sol ventrikül fonksiyonlari uzerine etkisi olabilir mi?

OBJECTIVE: The role of coronary collateral circulation (CCC) on the improvement of left ventricular function in coronary artery disease is controversial. The aim of this study is to investigate the effect of CCC on left ventricular function in patients with ischaemic heart disease. METHODS: Accordingly, 76 patients (39 female, 37 male, mean age--61 +/- 17 years) who had single vessel disease with > 85% narrowing in left anterior descending coronary artery were enrolled in this study. Coronary collateral circulation was determined according to the Rentrop classification (Class 0 = no collateral circulation; class 1 = small branches of occluded vessel fill with CCC; class 2 = epicardial segment of the occluded vessel partially fills with CCC; class 3 = epicardial segment of the occluded vessel totally fills with CCC). Left ventricular function was assessed with echocardiography and left ventricular regional wall motion score (0 = normokinetic; 1 = hypokinetic; 2 = akinetic; 3 = dyskinetic; 4 = aneurysmatic). Rentrop classification of the patients were compared with left ventricular regional wall motion scores and ejection fractions. RESULTS: Twenty one of 76 patients had no collateral circulation. The regional wall motion score of class 0 patients was similar with that of patients with CCC (class 1,2,3) (2.28 +/- 2.1 vs 3.39 +/- 2.1, p > 0.05). Particularly, the regional wall motion score was positively correlated with Rentrop classes (p < 0.05). Class 3 patients had the highest wall motion score (4.24 +/- 2.5, p < 0.05). Patients with and without CCC had similar left ventricular ejection fractions (49 +/- 11 vs 46 +/- 17, p > 0.05). CONCLUSION: This study showed that development of CCC has no preventive effect on left ventricular functions in patients with coronary artery disease. Interestingly as the stage of CCC increases left ventricular function worsens. It may be the result of the fact that patients with well developed CCC have more severe coronary artery disease.

[Do mobile telephones have adverse effects on the functions of implantable cardioverter defibrillators?]. / Mobil telefonlarin implante edilebilen kardiyoverter-defibrilatör fonksiyonlari uzerinde olumsuz etkileri olabilir mi?

OBJECTIVE: The aim of this study was to investigate the effects of widely used mobile telephones on the functions of implantable cardioverter-defibrillators (ICD). METHODS: The study included 9 patients (2 women, 7 men, mean age 65.5 +/- 6) with coronary artery disease who had underwent transvenous ICD implantation due to sustained ventricular tachycardia and/or fibrillation. First the test was performed on the basal conditions of ICD. Then, spontaneous heart rate of the patient was programmed to 10 beats/minute on VVI mode and the test was repeated. Two mobile telephones were located symmetrically 50 cm, 30 cm, 20 cm and 10 cm away from the ICD pocket in the pectoralis muscle and finally the mobile telephones antennas were touched to the pockets. On these different distances, the test was repeated during opening, standby, calling, talking and closing of the telephones. Possible ICD dysfunctions such as improper antitachycardic shock, inhibition of pacemaker functions, conversion to ventricular asynchronous mode (VOO) and development of ventricular trigger in devices with two chamber pacemaker functions were tested. The changes were observed on intracardiac and surface ECG's. RESULTS: There were no changes in the basal and pacemaker functions of ICD's and no symptoms in any patients. CONCLUSION: We have concluded that mobile telephones have no adverse effects on the functions of types of ICD assessed in the study.

Distribution of coronary artery lesions in patients with permanent pacemakers.

OBJECTIVE: In the present study we examined retrospectively the coronary anatomy pathology of 78 consecutive patients with coronary artery disease (CAD) who underwent permanent pacemaker implantation in order to find a common pathological anatomic basis for conduction disturbances and to compare them with a group of matched patients with angiographically proven CAD. METHODS: Study group consists of seventy-eight patients with angiographically documented CAD and permanent pacemaker implantation. Control group included comparable patients with CAD and without a pacemaker implantation. Coronary angiography was performed using standard Judkins approach in all patients within 2 months before pacemaker implantation. The locations of narrowings in the left anterior descending (LAD) and right (RCA) coronary arteries, as the arteries supplying the conduction system, were documented accurately and further classified as follows. Type I: Anatomy not compromising blood supply to the conduction system, namely, either the absence of significant narrowing in the LAD, RCA, left circumflex, posterolateral, or posterior descending arteries or the presence of mid-distal LAD lesions beyond the septal branches. Type II: Pathological coronary anatomy involving septal branches emerging from the LAD (and without significant lesions in the RCA). Type III: Pathological coronary anatomy compromising blood supply to the sinoatrial (SAN) or atrioventricular (AVN) nodes but not compromising blood flow to the septal branches. This subset included patients with distal LAD lesions after the septal branches. Type IV: Combination of types II and III pathological coronary anatomy that compromises blood supply both to the septal branches and SAN and AVN arteries. RESULTS: Occurrence of the type IV coronary anatomy (45%) was significantly higher than type I (19%), type II(24%) and type III (11%) in the study group (p<0.02). Statistically significant differences were found between the two groups (p<0.05): more patients in the study group had type II (24%) and IV(45%) coronary anatomy (p<0.02) while type I (35%) and III (37%) anatomy were more frequently observed in control group (p<0.05). Analysis of flow quality of septal perforators, SAN and AVN arteries, in the study group demonstrated a significant tendency for reduced blood flow in the conduction system. CONCLUSION: Presence of first perforator lesions with poor quality of flow and right coronary artery lesions shown angiographically should be considered as the risk factors requiring permanent pacemaker implantation in patients with coronary artery disease.

Echocardiographic features of patients with paroxysmal atrial fibrillation.

BACKGROUND: There are several risk factors for the initiation of paroxysmal atrial fibrillation (PAF) and the underlying mechanisms are multifactorial. Our study aims to explore the echocardiographic parameters that can identify in patients with PAF compared to normal subjects. METHODS: Eighty consecutive patients who were with PAF detected by 24-h Holter monitoring (HM) were assigned in our study. The control group (n = 80) consisted individuals with no PAF on HM. Indication for HM was palpitations at rest. All patients underwent routine echocardiographic evaluation. Patients with aortic and mitral stenosis, hyperthyroidism, and hypothyroidism were excluded from the study. Comprehensive clinical data were collected. RESULTS: Mean age of the patients with PAF was 63 +/- 11 years and of those 42% were male subjects. There was no difference in the prevalence of hypertension in both groups. Mean left ventricular ejection fraction (LVEF) was 57 +/- 15% in PAF group and 64 +/- 2% in control subjects (p < 0.001). Mean values of left atrial (LA) diameter for PAF and control groups were 3.7 +/- 0.6 cm vs. 3.1 +/- 0.4 cm (p < 0.001), respectively. Patients with PAF had more severe valve insufficiency, higher values of mean pulmonary artery systolic pressures (PAP) (29 +/- 10 mmHg vs. 25 +/- 2 mmHg, respectively; p = 0.001) and deteriorated MV inflow velocities (E:A ratio 0.9 +/- 0.4 vs. 1.1 +/- 0.3, respectively; p = 0.008) when compared to control group. In multivariate logistic regression analysis, LA diameter predicted the development of PAF after adjusted for age and gender. CONCLUSION: Our results indicate that LA diameter predicts the development of PAF.

Coronary collateral circulation: any effect on P-wave dispersion?

Coronary collateral circulation determines the severity of ischemic myocardial damage. Increased P-wave dispersion is an independent predictor for atrial fibrillation. Consistent evidence is little about the relation between coronary collateral circulation and arrhythmia risk. In this article, the effect of coronary collateral circulation on P-wave dispersion was evaluated. Collateral grade and P-wave dispersion were ascertained in 100 patients with >or=85% diameter stenoses in left anterior descending or right coronary arteries. Left ventricular function score was also determined in all patients. Coronary collateral circulation was absent in 32 patients, whereas 68 patients had coronary collateral circulation. Patients with collateral grade >or=1 had greater left ventricular function score than did patients with collateral grade 0 (P = .048). However, there was no significant difference between P-wave dispersion of patients with and without coronary collateral circulation (P = .45). The presence of coronary collateral circulation failed to exert a beneficial decreasing effect on P-wave dispersion.

Altered autonomic neural control of the cardiovascular system in patients with polycystic ovary syndrome.

PURPOSE: Polycystic ovary syndrome (PCOS) is frequently accompanied by the presence of cardiovascular risk factors. It has also been recognized that there is a significant relationship between the autonomic nervous system and adverse cardiac events. Heart rate recovery (HRR) after exercise is a marker of parasympathetic activity and attenuation of this parameter has been shown to be associated with increased cardiac mortality. A delayed recovery of systolic blood pressure (SBP) after peak exercise has been found to have diagnostic value and might reflect sympathetic hyperactivity. The analysis of variations in heart rate has also been used to determine the balance between sympathetic and vagal nerve activities in the heart. Our objective was to determine HRR, the SBP response to exercise and heart rate variability (HRV) in patients with PCOS. METHODS: The study population consisted of 26 untreated patients with PCOS and 24 healthy controls who were matched with respect to age, body mass index and physical activity. All subjects underwent symptom-limited exercise tolerance test according to a modified Bruce protocol. Following peak exercise, subjects walked a 2-min cool-down period. Heart rate recovery was calculated as the difference between heart rate at peak exercise and heart rate at the relevant minute of recovery. Blood pressure recovery indexes were determined by dividing the systolic blood pressure at 1, 2 and 3 min in recovery to the systolic blood pressure at peak exercise. RESULTS: HRR at 1 min (HRR1) of the patients with PCOS were significantly lower than that of controls (20+/-4 vs 28+/-8 bpm, p<0.0001). Although, resting SBP of the two groups were similar (117+/-7 vs 117+/-10 mmHg, p=0.663), the SBP of the patients with PCOS at peak exercise were significantly higher when compared to controls (172+/-12 vs 156+/-14 mmHg, p<0.0001). In addition, the SBP of the patients with PCOS remained significantly elevated when compared to controls at the first, second and third minute of recovery (168+/-13 vs 148+/-15 mmHg, 162+/-13 vs 136+/-16 mmHg, 152+/-17 vs 127+/-15 mmHg, respectively, p<0.0001 for all three). The SBP recovery index at 2 and 3 min of the patients with PCOS were significantly higher than that of controls (0.93+/-0.04 vs 0.87+/-0.07, p<0.0001 and 0.87+/-0.07 vs 0.82+/-0.09, p=0.017, respectively). Both time domain and frequency domain parameters of patients with PCOS were significantly lower than that of controls. CONCLUSION: This study shows that the patients with PCOS have attenuated HRR1, exaggerated SBP response to exercise which is delayed to recover and a depressed HRV. These findings might also suggest alterations in autonomic neurol control of the cardiovascular system in this disorder.

Coronary and systemic stent embolization during percutaneous coronary interventions: a single center experience.

OBJECTIVE: In this study, we attempted to analyze the incidence and outcomes of systemic and coronary stent embolizations during percutaneous coronary interventions and have described the treatment and retrieval methods used. METHODS: We retrospectively studied 24,038 consecutive coronary angiography procedures carried out at The Baskent University Adana Hospital from 1998 to present to determine the total number of stent embolization events. RESULTS: Among them, 4,797 were consecutive coronary stent operations and embolization was encountered in 14 cases (0.29%; 95% CI = 0.14-0.44%, P < 0.0001). The mean age of the patients was 61 +/- 8 years and 78% were men. Stent embolization occurred more frequently in cases with significant proximal angulation. Calcified lesions were not noted in any of the cases. In 7 out of 14 cases, stent embolization occurred at an unknown location and the clinical course was uneventful thereafter. Treatment and retrieval methods of the other 7 cases included the following: 1. Emergency cardiac bypass surgery (3 cases, 43%) 2. Advancement of a low profile delivery balloon through the stent, inflating the balloon, and replacing the stent at the lesion site (3 cases, 43%) 3. Crushing the stent against the coronary wall using another stent (1 case, 14%) 4. 4-loop snare (1 case, failed) None of the cases had bleeding that required transfusion. The stent was not crushed or deployed in the coronary artery causing major cardiac complication in any case. CONCLUSION: Systemic and coronary embolizations of stent procedures are rare. Consequences of coronary stent embolization can lead to prompt cardiac bypass surgery if the retrieval or deployment methods fail. Stent deployment or crushing techniques may be attempted before retrieval in patients who do not suffer from coronary thrombosis and myocardial infarction due to stent embolization.

Right ventricular penetration and cardiac tamponade as a late complication of Kirschner wire placement in the sternoclavicular joint.

A 44-year-old woman was admitted to the emergency service with dyspnea, chest pain, and vomiting. Cardiac tamponade due to right ventricular penetration of a Kirschner wire was detected as a late complication of wire placement in the sternoclavicular joint. Clinicians should be aware of wire migration with cardiac penetration as a late complication of Kirschner wire placed in any part of the body.

Decreased serum lipoprotein levels as a guide for clinical severity in patients with idiopathic dilated cardiomyopathy.

Hyperlipidemia is a cardiovascular risk factor. In patients with idiopathic dilated cardiomyopathy (IDC), prognostic roles of endogenous lipoproteins are not fully clarified. It has been known that there is a direct relationship between the levels of cytokines (tumor necrosis factor-alpha [TNF-alpha] and interleukin-6 [IL-6]) and deteriorating functional classes of heart failure and mortality. The present study compared the levels of circulating TNF-alpha, IL-6, lipoproteins, and apolipoproteins in patients with stable IDC (n = 28) with those of patients with unstable IDC (n = 26) and controls (n = 24). Mean serum total cholesterol (TC) was significantly lower in stable IDC patients than controls (p < 0.05). In unstable IDC patients, mean serum TC was also lower than controls but not statistically significant. The IDC patients had significantly higher concentrations of IL-6 and TNF-alpha than the controls (p < 0.01). Serum IL-6 and Apo AI levels were significantly different between stable and unstable IDC patients (p = 0.021 and p = 0.012, respectively). Increased levels of IL-6 were associated with decreased levels of TC (r = -0.266, p = 0.019), LDL-C (r = -0.376, p = 0.001) and apolipoprotein AI (apo AI) (r = -0.495, p < 0.001) in all IDC patients. TNF-alpha was also inversely related to apo AI (r = -0.455, p < 0.001) and LDL-C (r = -0.364, p = 0.001) in all patients. Thus, elevated serum levels of cytokines in patients with IDC are associated with decreased lipoprotein concentrations, which may indicate impaired prognosis.

Effects of slow coronary artery flow on QT interval duration and dispersion.

BACKGROUND: The coronary slow-flow phenomenon is an angiographic phenomenon characterized by delayed opacification of vessels in the absence of any evidence of obstructive epicardial coronary disease. Several studies have demonstrated myocardial ischemia in patients with slow coronary artery flow. In the present study, we aimed at evaluating the effects of slow coronary artery flow on QT interval duration and QT dispersion as a possible indicator of increased risk for ventricular arrhythmias and sudden cardiac death. METHODS: The study population included 49 patients with angiographically proven normal coronary arteries and slow coronary flow in all three coronary vessels (group I, 33 males, 16 females, mean age = 48 +/- 9 years), and 71 patients with angiographically proven normal coronary arteries without associated slow coronary flow (group II, 47 males, 24 females, mean age = 50 +/- 8 years). Coronary flow rates of all subjects were documented by thrombolysis in myocardial infarction frame count (TIMI frame count). QT interval duration and QT dispersion of all subjects were measured on the standard 12-lead electrocardiogram. RESULTS: There was no statistically significant difference between the two groups in respect to age, gender, presence of hypertension, and diabetes mellitus. There was a significant difference between the two groups in respect to the presence of cigarette smoking, typical angina, and positive exercise test results. TIMI frame counts of group I patients were significantly higher than those of group II patients for all three coronary arteries (P < 0.001). Maximum corrected QT interval (QTcmax) of group I did not differ from the QTcmax of group II (P > 0.05). However, minimum corrected QT interval (QTcmin) of group I was significantly lower than that for group II (P = 0.008). Consequently, corrected QT dispersion (QTcd) in group I was found to be significantly higher than in group II (P < 0.001). CONCLUSION: QTcd, indicating increased risk for ventricular arrhythmias and cardiovascular mortality, was found to be significantly higher in patients with slow coronary artery flow. However, further long-term prospective studies should be carried out to establish the significance of QTcd as a risk factor for ventricular arrhythmias and subsequent sudden cardiac death in patients with slow coronary artery flow.