Effect of balloon-induced acute ischaemia on P wave dispersion during percutaneous transluminal coronary angioplasty.

AIMS: P wave dispersion is a recent ECG marker that reflects discontinuous and inhomogeneous conduction of sinus impulses, which has been studied in a limited number of cardiac conditions. The aim of our study was to investigate the effects of angioplasty induced-ischaemia on atrial conduction abnormalities as estimated by P maximum and P dispersion. METHODS AND RESULTS: The study consisted of 67 consecutive patients (41 men, mean age 58 +/- 11 years) with 1-vessel coronary artery disease who underwent elective single vessel coronary angioplasty (left anterior descending (LAD) coronary artery in 28 patients, the right coronary artery (RCA) in 22 patients and the left circumflex coronary artery (LCx) in 17 patients. All patients underwent 12-lead surface ECG before the first inflation (baseline) and then 60 s after intra-coronary balloon inflation. The maximum P wave duration, the minimum P wave duration, and P wave dispersion (Pd=Pmax - Pmin) were calculated from 12-lead surface ECGs. Baseline P wave duration measurements were not significantly different among the patients with LAD, RCA and LCx coronary artery disease (P>0.05). P dispersion and P maximum were significantly higher during balloon occlusion compared with the baseline condition in all three types of coronary dilatation procedures. However, P minimum was not found to differ between baseline and during balloon occlusion (P>0.05). CONCLUSION: The prolongation of P wave dispersion may be a useful and simple additional marker for myocardial ischaemia.

Extent of coronary atherosclerosis and homocysteine affect endothelial markers.

The aim of the study was to evaluate the effects of the presence, extent, and clinical stability of coronary artery disease on endothelial function parameters, C-reactive protein and homocysteine levels. Fifty-eight patients with angiographically documented coronary artery disease and 25 patients with normal coronary arteries were evaluated for risk factors, plasma homocysteine, C-reactive protein, and soluble adhesion molecule levels. Vascular cell adhesion molecule-1 and sE-selectin were significantly higher in the group with coronary artery disease than in healthy subjects (p = 0.005 and p = 0.031, respectively). Patients with unstable angina had significantly higher C-reactive protein (p < 0.001), troponin I (p < 0.01), and leukocyte counts (p < 0.05) than those with stable angina. sE-selectin levels were correlated with the extent of coronary atherosclerosis (r = 0.444, p < 0.05), and plasma homocysteine levels were associated with vascular cell adhesion molecule-1 (r = 0.479, p < 0.05) in unstable cases. These results suggest that vascular cell adhesion molecule-1 and sE-selectin are useful for determining the presence of coronary atherosclerosis, whereas C-reactive protein, troponin 1, and leukocyte count are predictors of clinical stability.

No evidence of cardiac autonomic involvement in ankylosing spondylitis, as assessed by heart rate variability.

The aim of this study was to investigate the involvement of autonomic nervous system (ANS) function by using power spectral analysis of heart rate variability (HRV) method in patients with ankylosing spondylitis (AS). The study included 94 AS patients all fulfilling the New York criteria for AS, and 49 healthy volunteers. Recordings for HRV were obtained with a PC-based high-resolution electrocardiographic system and analysed using power spectral analysis. The peak around 0.04-0.15 Hz was defined as low-frequency peak (LF) and the other, around 0. 15-0.40 Hz, was defined as high-frequency peak (HF), representing mostly the sympathetic and the parasympathetic components of the ANS, respectively. The following variables were calculated and compared between groups: the LF in absolute and normalised units (LF nU); the HF in absolute and normalised units (HF nU); and LF/HF ratio. The AS group included 47 male and 47 female subjects with a mean age of 33 +/- 11 years (range 16-64). In the control group there were 23 male and 26 female healthy subjects (mean age 33 +/- 8; range 19-60). None of the patients or control subjects had any cardiac or neurological symptoms. Both groups were similar with respect to age and sex characteristics (p > 0.05). The HRV analysis indicated that the peaks of LF, LF nU, HF, HF nU and LF/HF ratio were similar in both groups. Groups also did not differ with respect to heart rate at the time of examination. Our data demonstrated no evidence of ANS involvement as assessed by HRV analysis in AS patients.

Percutaneous balloon pericardiotomy for patients with malignant pericardial effusion including three malignant pleural mesotheliomas.

Ten patients were enrolled in this study to evaluate the therapeutic value of percutaneous balloon pericardiotomy in patients with symptomatic pericardial effusion secondary to malignant diseases. Four patients had breast cancer; 2 had lung cancer; 1 had non-Hodgkin's lymphoma; and 3 had malignant pleural mesothelioma, which is commonly seen in Central Anatolian region of Turkey. All patients underwent percutaneous balloon pericardiotomy with monofoil balloons (Mansfield, NuMed). No complication was seen during these procedures. In 3 patients, the balloon could not be expanded completely and was entered from a more lateral position by a second puncture. There was no recurrence of pericardial effusion in 6 of 7 patients without mesothelioma. After percutaneous balloon pericardiotomy, surgical subxiphoid windowing was performed due to drainage greater than 100 mL/day in a patient with lung cancer and in 1 patient with mesothelioma. In the other 2 patients with mesothelioma, recurrence of pericardial effusion was seen and then subxiphoid surgical windowing was performed due to development of cardiac tamponade in 1 of them. All the patients died 68.6 +/- 36 days later due to the primary malignancies. The survival time of patients with mesothelioma was shorter than that of the others (p < 0.05). These results suggest that percutaneous balloon pericardiotomy may be used in the treatment of patients with malignant pericardial effusion as an alternative to surgical pericardial window creation. But in patients with malignant pleural mesothelioma, the success rate of this procedure was lower than that of the others.

Acute anterior myocardial infarction following a mild nonpenetrating chest trauma--a case report.

Myocardial infarction in patients under age 45 years is a relatively unusual phenomenon; blunt chest trauma is one of the nonatherosclerotic mechanisms leading to acute myocardial infarction in young adults. The authors report a rare case of anterior myocardial infarction in a 22-year-old man following a mild nonpenetrating chest trauma whose left chest was elbowed during a soccer game.

Platelet and leukocyte deactivation after intracoronary stent placement in patients receiving combined antiplatelet therapy.

Activated platelets and leukocytes have been demonstrated to play a role in the development of stent thrombosis, and coronary angioplasty has been shown to result in activation of platelets, leukocytes, and endothelial cells. We aimed to evaluate the effects of intracoronary stent placement and aspirin plus ticlopidine treatment on platelets, leukocytes, and endothelial cells via observing the serial changes in the circulating soluble forms of adhesion molecules in 54 patients with coronary artery disease, who had elective coronary angioplasty and stent implantation for a single lesion of the left anterior descending artery. After stent placement, intravenous heparin infusion was administered only for 24 hours, and aspirin plus ticlopidine treatment was applied for 1 month. Venous blood samples were drawn before stent placement, and repeated 24 and 48 hours after the procedure. Patients were excluded if they had had recent cardiovascular events or any illness that might influence platelet, leukocyte, and endothelial cell function. The plasma level of sL-selectin was significantly decreased 48 hours after coronary stenting (636+/-110 ng/mL vs 567+/-93 ng/mL; P = 0.001, respectively). Likewise, the plasma level of sP-selectin was also decreased significantly 48 hours after the procedure (260+/-61 ng/mL vs 233+/-83 ng/mL, P = 0.01). The sE-selectin level was found to be significantly increased 24 hours (31+/-9 ng/mL vs 39+/-12 ng/mL, P = 0.0001) and 48hours(31+/-9 ng/mL vs 42+/-15 ng/mL, P = 0.001) after coronary stenting. The results of our study suggest that significant platelet and leukocyte deactivation take place in patients treated with combined antiplatelet therapy after stenting; endothelial cell activation also occurs during this treatment.

Hydatid cyst of the heart as a rare cause of embolization: report of 5 cases and review of published reports.

Cardiac hydatid cyst is seen infrequently, even in regions where hydatid cysts are endemic. We report 5 cases of cardiac hydatid cysts, which were diagnosed after an embolic event.

Increased plasma levels of soluble selectins in patients with unstable angina.

BACKGROUND: Inflammation plays an important role in the pathogenesis of unstable angina. Adhesion molecules, such as selectins, mediate the interactions between leukocytes, platelets and endothelial cells during inflammation and thrombogenesis. HYPOTHESIS: The purpose of this study was to determine whether soluble E-selectin, P-selectin and L-selectin levels are increased in patients with unstable angina (UA). METHODS: Soluble E-, P- and L-selectin levels were measured by enzyme-linked immunoassay in the peripheral blood of 23 patients with UA, 26 patients with stable angina (SA) and 15 control patients with angiographically normal coronary arteries. RESULTS: Soluble E-selectin levels were significantly higher in patients with UA (45+/-11 ng/ml) than in controls (30+/-8 ng/ml, P<0.001), or patients with SA (34+/-8 ng/ml, P=0.001). Similarly, plasma levels of P- and L-selectin were significantly higher in patients with UA (427+/-144 and 772+/-160 ng/ml, respectively) than in patients with SA (278+/-79 and 643+/-94 ng/ml, respectively, P<0.005 vs. UA for both), or control patients (189+/-43 and 601+/-126 ng/ml, respectively, P=0.001 vs. UA for both). CONCLUSIONS: Plasma levels of soluble selectins were increased in patients with UA compared with patients with SA or patients without angiographically visible coronary artery disease. Measurements of these adhesion molecules may be helpful as non-invasive markers of coronary plaque destabilization in UA.

Effects of stent coating on platelets and endothelial cells after intracoronary stent implantation.

BACKGROUND: Adhesion molecules are known to be important in the regulation of endothelial cell and platelet functions. Increased platelets P-selectin expression is a marker of stent thrombosis after uncoated stent placement. HYPOTHESIS: The aim of this study was to compare the effects of intracoronary placement of phosphorylcholine (PC)-coated, versus heparin-coated, versus uncoated stents on platelets and endothelial activity. METHODS: Thirty patients (age 55 +/- 10, 27 men) with significant proximal left anterior descending coronary artery stenoses were randomized to elective implantation of PC-coated, versus heparin-coated, versus uncoated stents. Following stent placement, intravenous heparin and aspirin plus ticlopidine were administered. Venous plasma soluble E-selectin, sP-selectin, and intercellular adhesion molecule-l levels were measured before the procedure and 24 and 48 h thereafter as markers of platelet and endothelial cell activation. Patients were excluded if they had a disease known to influence platelet and endothelial cell function. RESULTS: Plasma sP-selectin levels decreased significantly after implantation of PC- and heparin-coated stents (p = 0.04), but remained unchanged in patients randomized to uncoated stents. Plasma sE-selectin levels increased significantly after uncoated stent placement (p = 0.04) and remained unchanged after coated stent implantation. CONCLUSION: In patients treated with combined antiplatelet therapy, implantation of PC- and heparin-coated stents decreased platelet activity without activating endothelial cells, whereas placement of uncoated stents led to endothelial activation without changing platelet activity. These results suggest that PC-coated and heparin-coated stents may be advantageous in limiting thrombotic complications.

T wave alternans can decrease after coronary revascularization.

Clinical observations and animal experiments indicate that T wave alternans (TWA) is associated with an increased propensity for ventricular fibrillation, and thus it may be considered as a noninvasive marker of life-threatening ventricular arrhythmias. There is substantial evidence indicating that TWA is an intrinsic property of ischemic myocardium. This study was performed to determine the role of percutaneous transluminal coronary angioplasty (PTCA)-induced myocardial ischemia in the development of TWA and the effects of revascularization. The authors recorded bipolar X, Y, and Z leads of 111 consecutive patients (mean age: 56 years) undergoing PTCA before, during, and 24 hours after the procedure. T wave alternans signal was calculated in 97 patients (43 left anterior descending, 26 right coronary artery, and 28 circumflex or major obtuse margin branch) by fast Fourier transformation technique after signal processing. Twenty-four hours after the procedure, the mean and peak X, Y, and Z values for TWA had all been significantly reduced from baseline and during balloon inflation (p<0.01). The findings point out that induced ischemia could be a trigger for T wave alternans, and successful revascularization can reduce alternans.

QT dispersion as a predictor of arrhythmic events in patients with ankylosing spondylitis.

OBJECTIVE: The aim of the study was to evaluate QT dispersion (QTd), an indicator of repolarization heterogeneity, and its relation to ventricular arrhythmias in patients with ankylosing spondylitis (AS). METHODS: A full history, clinical examination, electrocardiograms and 24-h Holter monitoring were performed in 88 AS patients and 31 volunteers of similar age and sex. Groups were compared based on electrocardiographic abnormality, QTd, arrhythmias and heart blocks. RESULTS: QTd and corrected QTd (QTcd) were significantly greater in AS patients than controls (QTd, 52.8 +/- 15.1 vs 35.5 +/- 8.9 ms, P: < 0.0001; QTcd, 60.3 +/- 16.1 vs 39.4 +/- 10.7 ms, P: < 0.0001). The magnitudes of these parameters were associated with the duration of the disease (QTd, r = 0.56, P: < 0.01; QTcd, r = 0.60, P: < 0.001). The frequency of ventricular extrasystoles was found to be correlated with QTd (r = 0.35, P: < 0.01) and QTcd (r = 0.33, P: < 0. 01). CONCLUSION: Involvement of the heart may be seen in AS during the early clinical course of the disease. QTd may give clues about the presence of arrhythmias and can be used as a new technique for the evaluation of asymptomatic patients. Earlier detection of cardiac involvement could alter the prognosis of the patients.

Assessment of autonomic nervous system functions in patients with vitamin B12 deficiency by power spectral analysis of heart rate variability.

The purpose of this study was to test the autonomic nervous system function of patients with vitamin B12 deficiency (megaloblastic anemia) by measuring heart rate variability (HRV). The study population consisted of 17 vitamin B12 deficient patients and 15 age- and sex-matched normal volunteers. HRV was measured by power spectral analysis from which power of the low frequency (LF) peak (0.04-0.15 Hz), normalized units of the LF peak (LFNU), power of the high frequency (HF) peak (0.15-0.4 Hz), normalized units of the HF (HFNU), and ratio of power of LF to power of HF (LF:HF) were calculated. Vitamin B12 deficient patients had lower LF, LFNU, HF, HFNU, and LF:HF ratio than normal volunteers (P < 0.05). Decreases in sympathetic indices (LF and LFNU) were greater than those measured in parasympathetic indices (HF and HFNU). All HRV parameters correlated positively with the level of vitamin B12 (P < 0.001) and negatively with the duration of disease (P < 0.001). After vitamin B12 replacement the HRV parameters of patients and controls became comparable (P > 0.05). Our data suggest that autonomic sympathetic and parasympathetic nervous activities are decreased in patients with vitamin B12 deficiency, an abnormality that can be corrected by vitamin B12 replacement therapy.

P wave dispersion on 12-lead electrocardiography in patients with paroxysmal atrial fibrillation.

The prolongation of intraatrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses have been shown in patients with atrial fibrillation. Recently P wave dispersion (PWD), which is believed to reflect inhomogeneous atrial conduction, has been proposed as being useful for the prediction of paroxysmal atrial fibrillation (PAF). Ninety consecutive patients (46 men, 44 women; aged 55 +/- 13 years) with a history of idiopathic PAF and 70 healthy subjects (42 men, 28 women; mean age 53 +/- 14 years) were studied. The P wave duration was calculated in all 12 leads of the surface ECG. The difference between the maximum and minimum P wave duration was calculated and this difference was defined as P wave dispersion (PWD = Pmax-Pmin). All patients and controls were also evaluated by echocardiography to measure the left atrial diameter and left ventricular ejection fraction (LVEF). There was no difference between patients and controls in gender (P = 0.26), age (P = 0.12), LVEF (66 +/- 4% vs 67 +/- 5%, P = 0.8) and left atrial diameter (36 +/- 4 mm vs 34 +/- 6 mm, P = 0.13). P maximum duration was found to be significantly higher in patients with a history of PAF (116 +/- 17 ms) than controls (101 +/- 11 ms, P < 0.001). P wave dispersion was also significantly higher in patients than in controls (44 +/- 15 ms vs 27 +/- 10 ms, P < 0.001). There was a weak correlation between age and P wave dispersion (r = 0.27, P < 0.001). A P maximum value of 106 ms separated patients with PAF from control subjects with a sensitivity of 83%, a specificity of 72%, and a positive predictive accuracy of 79%. A P wave dispersion value of 36 ms separated patients from control subjects with a sensitivity of 77%, a specificity of 82%, and a positive predictive accuracy of 85%. In conclusion, P maximum duration and P wave dispersion calculated on a standard surface ECG are simple ECG markers that could be used to identify the patients with idiopathic paroxysmal atrial fibrillation.

Left atrial appendage function in patients with cardioembolic stroke in sinus rhythm and atrial fibrillation.

The purpose of this study was to determine the left atrial appendage (LAA) function in patients with stroke. The study group consisted of 61 patients with stroke and 37 control subjects. Patients with stroke were divided into 2 groups on the basis of the presence of atrial fibrillation (group 1) or sinus rhythm (group 2). Group 1 showed a significant reduction of LAA flow velocities (13.2 +/- 6.4 cm/s versus 27.5 +/- 8 cm/s, P <.05) and significant increase in LAA areas (minimum area: 360.5 +/- 204 mm(2) versus 217.7 +/- 113.9 mm(2), P =.004). Group 2 showed a decrease in LAA flow velocities (17.7 +/- 8.2 cm/s versus 27.5 +/- 8 cm/s, P <.05), but no significant change was found in LAA areas. No significant difference was found in other parameters related to LAA. These findings show that a decreased LAA flow velocity is a risk factor for stroke in patients in sinus rhythm without LAA enlargement. Left atrial appendage area was increased in size only in patients with atrial fibrillation.

Effects of glibenclamide, a K(ATP) channel blocker, on warm-up phenomenon in type II diabetic patients with chronic stable angina pectoris.

BACKGROUND: Warm-up phenomenon, one of the clinical models of ischemic preconditioning, refers to an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. HYPOTHESIS: Blockers of K(ATP) channels, such as the sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects of glibenclamide, a sulfonylurea with a high affinity for myocardial K(ATP) channels, on the results of two consecutive exercise tests in diabetic patients with coronary artery disease. METHODS: Eighteen type II diabetic patients with chronic stable angina pectoris participated in this study. All patients underwent two consecutive treadmill exercise tests with a recovery period of 15 min in fasting state. On the day after these exercise tests, 10 mg oral glibenclamide was given to the same patients and 30 min later 200 ml of 30% glucose solution was given orally. Half an hour later, which is the time of peak plasma levels of glibenclamide, two exercise tests were repeated consecutively with a 15 min recovery period. RESULTS: There was no difference in blood glucose levels before and after exercise tests on each day (p > 0.05). Without glibenclamide, heart rate, rate-pressure product at 1.5 mm ST depression, and peak exercise increased significantly (p < 0.05). Time to 1.5 mm ST-segment depression and onset of pain, as well as duration of exercise also increased, but ST-segment depression and ST-recovery time significantly decreased (p < 0.05). In contrast, these values did not significantly change after glibenclamide (p>0.05), with a significant drug-test interaction (p < 0.05, at two-way ANOVA). CONCLUSIONS: Glibenclamide, an oral hypoglycemic agent with a K(ATP) channel-blocker activity, with a 10 mg oral dose, abolished the warm-up phenomenon which is a clinical finding of ischemic preconditioning on two consecutive exercise tests. Therefore, glibenclamide should be used carefully in patients with coronary heart disease and diabetes mellitus since this agent leads to a decrease in ischemic threshold and exercise capacity.

Is ventricular repolarization heterogeneity a cause of serious ventricular tachyarrhythmias in aortic valve stenosis?

BACKGROUND: It is well known that there is a close relation between sudden cardiac death and serious ventricular tachyarrhythmias in patients with aortic valve stenosis (AS). QT dispersion (QTd) reflects the ventricular repolarization heterogeneity and has been proposed as an indicator for ventricular arrhythmias. HYPOTHESIS: This study investigated the QTd and its relevance to the clinical and echocardiographic variables. METHODS: In all, 51 patients (33 men, 18 women, mean age 56 +/- 12) with isolated AS and 51 age- and gender-matched healthy controls comprised the study group. Left ventricular mass index (LVMI) was calculated by the Devereux formula, and we used continuous-wave Doppler (n = 15) and cardiac catheterization (n = 36) for the determination of the maximum aortic valve pressure gradient (PG). RESULTS: Corrected QTd (QTcd) (89 +/- 39 vs. 49 +/- 15 ms, p < 0.001) and LVMI (176 +/- 69 g/m2 vs. 101 +/- 28 g/m2, p < 0.001) in patients with AS were significantly different from those in the control group. The group of 21 patients had a significantly greater number of 24-h mean ventricular premature beats (VPB) and mean number of couplet VT episodes than did the control group (p < 0.05). QTcd also correlated significantly well with LVMI (r = 0.58, p < 0.001), PG (r = 0.41, p = 0.003), and number of 24-h VPB (r = 0.56, p = 0.008). With respect to symptoms (e.g., angina, syncope, and dyspnea) patients without symptoms (n = 19) displayed less QTcd (71 +/- 31 vs. 100 +/- 39 ms, p = 0.007) and less LVMI (144 +/- 80 g/m2 vs. 195 +/- 57 g/m2, p = 0.01) than patients with symptoms. Statistical analysis was similar for all variables with uncorrected QTd values. CONCLUSION: We found that ventricular repolarization heterogeneity was greater in patients with AS than in controls. Our findings also showed that QTd in the patient group correlates well with LVMI, severity of AS, and PG. The present results suggest that serious ventricular arrhythmias in patients with AS may be due to spatial ventricular repolarization abnormality.

Echocardiographic findings of pericardial involvement in patients with malignant pleural mesothelioma with a history of environmental exposure to asbestos and erionite.

OBJECTIVE: The aim of the present study was to evaluate the pericardial involvement in patients with malignant mesothelioma caused by exposure to different minerals. METHODOLOGY: Forty-two patients (mean age of 52 +/- 12 years) with malignant mesothelioma were examined with transthoracic echocardiography. Thirty-three (78.9%) patients had a history of environmental exposure to asbestos and nine (21.4%) had a history of environmental exposure to erionite. RESULTS: In 19 (45.2%) patients with malignant pericardial mesothelioma, pericardial involvement was determined by echocardiography. The other 23 (54.8%) patients had no pericardial involvement. Pericardial effusion was detected in nine (64.3%) patients and pericardial effusion was small in six (14.3%) patients, moderate in one (2.4%) patient and large in two patients. Thickening of the pericardium was observed in eight (19%) patients. In another two (7.1%) patients pericardial calcification was observed. Among the 33 patients who had been exposed to asbestos, 15 (45.5%) had pericardial involvement, and among the nine patients with a history of exposure to erionite, four (44.4%) had pericardial involvement. There was no difference in terms of pericardial involvement in different stages of the tumour (P > 0.05). CONCLUSIONS: Pericardial involvement is commonly seen in patients with malignant mesothelioma. Among patients exposed to asbestos or zeolite there was no difference in terms of pericardial involvement. Furthermore, pericardial involvement was not related with the stage of the tumour.

Circulating adhesion molecules in patients with stable coronary artery disease.

To evaluate platelet and endothelial function in patients with stable coronary artery disease (CAD), we investigated levels of the plasma-soluble (s) adhesion molecules E-selectin (sE-selectin), P-selectin (sP-selectin), and intercellular adhesion molecule-1 (sICAM-1) in 74 patients (mean age, 53 +/- 8 years) with angiographically documented coronary artery disease. Levels were compared to 27 matched healthy control subjects. Patients were excluded if they had recent cardiovascular events or any illness that might influence platelet and endothelial cell function. Concentrations of sP-selectin were significantly higher in patients with stable CAD (276 +/- 61 ng/mL) compared with control subjects (188 +/- 32 ng/mL) (P = .0001), whereas sE-selectin and sICAM-1 levels were similar between the 2 groups. Pooling both groups showed that sICAM-1 correlated weakly with triglycerides (r = 0.240, P = .01) and sP-selectin correlated weakly with low-density lipoprotein cholesterol (r = 0.204, P = .04). Although plasma sICAM-1 concentrations were significantly increased in hypercholesterolemic patients compared with those of normocholesterolemic patients (P = .04), sP-selectin and sE-selectin levels were similar between the 2 groups. In conclusion, significantly increased sP-selectin levels, indicating platelet activation, were found in patients with stable CAD. No other sign of endothelial cell activation in these patients could be detected. Moreover, sP-selectin levels seem to reflect the activation of platelets rather than of endothelial cells.

P wave dispersion in hypertensive patients with paroxysmal atrial fibrillation.

It is important to assess the risk of developing paroxysmal atrial fibrillation (PAF) in hypertensive patients since hypertension is a common disorder predisposing to PAF. We sought to determine if patients with hypertension at risk of PAF can be identified while in sinus rhythm by measurements of P wave dispersion. Twelve-lead surface electrocardiograms were recorded in 44 hypertensive patients with history of PAF (group I, mean age = 60) and in 50 hypertensive patients without history of AF (group II, mean age = 57). The maximum P wave duration, the minimum P wave duration, and P wave dispersion (Pd = Pmax - Pmin) were calculated from 12-lead surface ECGs. Left atrial dimension (LAD) and left ventricular ejection fraction (LVEF) were measured by echocardiography. P wave dispersion was significantly greater in group I than group II (50 +/- 12 vs 38 +/- 8 ms, P = 0.001). P minimum (75 +/- 13 vs 87 +/- 11 ms, P = 0.001) and LVEF (0.63 +/- 0.05 vs 0.67 +/- 0.04, P = 0.03) were significantly lower in group I than group II. However P maximum and LAD were not significantly different in group I than group II (P > 0.05). In univariate analysis, P minimum, P wave dispersion, and LVEF were significant predictors of PAF, whereas only P wave dispersion remained a significant independent predictor of PAF in a multivariate analysis. Measurement of P wave dispersion in sinus rhythm may be a useful noninvasive clinical tool to identify patients with hypertension at risk of developing atrial electrical instability and atrial fibrillation.

Permanent left ventricular pacing from the great cardiac vein of a patient with artificial tricuspid and mitral valves--a case report.

Transvenous placement of a right ventricular pacemaker lead through the artificial tricuspid valve is a known contraindication, and in this situation, epicardial pacemaker implantation is the procedure of choice. However, permanent pacemaker implantation is a subject for debate when the use of the epicardial route is impossible. This report describes alternate transvenous routes for a pacemaker lead in a patient with an artificial tricuspid valve and mitral valve in whom the epicardial lead and pacemaker generator must be removed because of resistant infection.