High sensitivity CRP levels predict atrial tachyarrhythmias in rheumatic mitral stenosis.

BACKGROUND: The different levels of inflammation in rheumatic mitral stenosis determine its clinical consequences. Atrial fibrillation is frequently encountered in mitral stenosis, though the independent role of chronic inflammation in determining atrial tachyarrhythmia occurrence in rheumatic heart disease has not been demonstrated previously. METHODS: Measurements of C-reactive protein (CRP) with a high sensitivity assay to detect chronic inflammation were performed in a homogenous group of 50 patients with rheumatic mitral stenosis, who were in sinus rhythm. Patients were questioned to exclude confounders of CRP elevation. The patients underwent a twenty-four-hour ambulatory ECG monitoring to check for asymptomatic atrial tachyarrhythmias and were in addition classified according to the presence of atrial tachyarrhythmias. RESULTS: Forty-four percent of patients showed a total of 100 episodes of atrial tachyarrhythmias where 63% of these episodes were paroxysmal atrial fibrillation. The CRP values in patients with tachyarrhythmias were significantly higher than in patients who remained in sinus rhythm (4.2 +/- 0.55 mg/L vs 1.99 +/- 0.36 mg/L, P < 0.001). A logistic regression analysis revealed only CRP levels and previous history of mitral valvuloplasty significantly determined tachyarrhythmia occurrence where age, left atrial volumes, mitral gradients had no statistically significant effect. CONCLUSIONS: Our data implicated that nearly half of the mitral stenosis patients who are in sinus rhythm develop asymptomatic tachyarrhythmias and the higher levels of CRP in these patients show the significant effect of persistent inflammation on arrhythmia occurrence.

An electrocardiographic algorithm for determining the location of pacemaker electrode in patients with right bundle branch block configuration during permanent ventricular pacing.

The expected morphology of right ventricular pacing is a left bundle branch block (LBBB) pattern. However, right bundle branch block (RBBB) can also be seen during permanent right ventricular pacing. The aim of this study was to develop an electrocardiographic algorithm to differentiate this benign condition from septal and free wall perforation with subsequent left ventricular pacing. Three hundred consecutive patients who had permanent ventricular or dual-chamber pacemaker implantation between 1999 and 2000 were screened and 25 patients (8.3%) who exhibited RBBB configuration were included in the study. Echocardiograms and chest radiographs were evaluated in order to identify the pacing lead location in this group. The authors formed a study group with their own 25 patients and 22 cases of RBBB with permanent pacemaker from previous publications (total 47 patients). Frontal axis, QRS morphology in lead V(1), and the precordial transition point, which is defined as the precordial lead where R wave amplitude is equal to S wave amplitude, were examined. Placement of precordial leads V(1) and V(2) 1 interspace lower than the standard location (Klein maneuver) eliminated the RBBB pattern in 12 patients. RBBB pattern with "true right ventricular pacing" was detected in 24 of the 25 patients, and in 11 of the 22 patients reported in the literature (total 35 patients). Right ventricular pacing was correctly identified in 34 of 35 patients with use of criteria including left superior axis deviation, RS or qR morphology in lead V(1), and precordial transition at lead V(3) with a high sensitivity and specificity. A simple surface electrocardiogram can accurately predict the lead location in patients having RBBB morphology with right ventricular pacing.

Tricuspid valve perforation by permanent pacemaker lead--a case report.

Tricuspid valve perforation with pacemaker lead is one of the extremely rare complications of transvenous pacemaker implantation. Approximately all reported cases have been diagnosed at autopsy. The authors present a case of tricuspid valve perforation caused by pacemaker lead that was diagnosed during cardiac surgery and treated successfully by removing the lead and suturing the tricuspid valve.

Sequential evaluation of left ventricular systolic and diastolic function after radiofrequency catheter ablation.

Radiofrequency (RF) catheter ablation has become standard therapy for many types of arrhythmias. RF energy may cause deterioration in left ventricular function by damaging the myocardium. The aim of the present study was to assess the changes in left ventricular function after catheter ablation using various echocardiographic parameters. Forty patients (22 women), aged 37 +/- 14 years (range, 15-76 years), underwent catheter ablation for various tachycardias. Routine echocardiogaphic examination was done in all patients. Left ventricular systolic function was evaluated by the modified Simpson method and tissue Doppler. With regard to left ventricular diastolic function parameters, diastolic early (E) and late (A) transmitral filling velocities, deceleration time (DT), isovolumetric relaxation time (IVRT), and tissue Doppler parameters were assessed. All ventricular function parameters were assessed before, and 1 hour, 1 day, and 1 month after the catheter ablation procedure. To avoid any influence of heart rate on diastolic function parameters, the E/A ratio, DT, and IVRT were adjusted to heart rate (cE/A, cDT, cIVRT). No changes in left ventricular systolic function after the ablation were observed. After the ablation procedure (1 hour, 1 day, and 1 month) the cE/A ratio decreased from 1.42 +/- 0.43 to 1.19 +/- 0.40, 1.18 +/- 0.40, and 1.30 +/- 0.33 (P = 0.009), respectively. cDT increased from 210 +/- 54 to 272 +/- 64, 255 +/- 60, 240 +/- 64 (P = 0.001), respectively. Likewise cIVRT increased from 113 +/- 22 to 133 +/- 54, 123 +/- 27, 117 +/- 19 (P = 0.007), respectively. Significant changes were also observed concerning tissue Doppler parameters in assessing diastolic function. Although no significant changes were observed in systolic function after RF ablation, this procedure may have some detrimental effects on ventricular diastolic function para-meters.

Pacemaker related endocarditis: analysis of seven cases.

Vegetative electrode infection following permanent pacemaker implantation is a rare and serious complication. Among 1920 patients who underwent permanent pacemaker implantation in our institute between 1980 and 2000, 7 patients aged 65 to 78 years were diagnosed to have pacemaker related endocarditis. In this study, the clinical course and management strategies for these patients are reviewed. The most frequently encountered factors contributing to development of pacemaker infection were local complications such as postoperative hematoma and inflammation, and recurrent surgical interventions on the pacemaker system. In blood cultures S. aureus was the most common causative microorganism. Echocardiography could be performed in 5 patients. Three patients were referred to open-heart surgery for total removal of the pacemaker system, and one patient had his pacemaker system removed percutaneously. The remaining 3 patients did not agree to either surgical or percutaneous removal. These patients have been under antibiotic therapy for approximately 3 years and they still do not have any signs of a serious infection. Consequently, in patients with permanent pacemakers, infective endocarditis should be considered in the presence of fever and local symptoms. Blood cultures should be obtained and echocardiography should be performed. Complete removal of the pacemaker system with intensive antibiotic treatment is necessary for complete eradication of the infection. However, if percutaneous or surgical removal of the electrodes cannot be done because of high perioperative risk or the patient does not agree to undergo either method, medical treatment with long term antibiotic use may be considered as an alternative.

Differentiation of narrow QRS complex tachycardia types using the 12-lead electrocardiogram.

BACKGROUND: Previous studies have shown that only 80% of narrow QRS supraventricular tachycardia (SVT) types can be differentiated by standard 12-lead electrocardiographic (ECG) criteria. This study was designed to determine the value of some new ECG criteria in differentiating narrow QRS SVT. METHODS AND RESULTS: 120 ECGs demonstrating paroxysmal narrow QRS complex tachycardia (QRS < or = 0.11 ms and rate > 120 beats/min) were analyzed. Forty atrioventricular reciprocating tachycardia (AVRT), 70 atrioventricular nodal reentrant tachycardia (AVNRT), and 10 atrial tachycardia defined with electrophysiologic study (EPS) consisted the study group. Eight surface ECG criteria were found to be significantly different between tachycardia types by univariate analysis. P waves separate from the QRS complex were observed more frequently in AVRT (70%) and atrial tachycardia (80%). Pseudo r' deflection in lead V(1), pseudo S wave in inferior leads, and cycle length alternans were more common in AVNRT (55, 20, and 6%, respectively). QRS alternans was also present during AVRT (28%). ST-segment depression (> or = 2 mm) or T-wave inversion, or both, were present more often in AVRT (60%) than in AVNRT (27%). During sinus rhythm, manifest preexcitation was observed more often in patients with AVRT (42%). When a P wave was present, RP/PR interval ratio > 1 was more common in atrial tachycardia (90%). By multivariate analysis, presence of a P wave separate from the QRS complex, pseudo r' deflection in lead V(1), QRS alternans, preexcitation during sinus rhythm, ST-segment depression > 2 mm or T-wave inversion, or both, were independent predictors of tachycardia type. CONCLUSIONS: Several new ECG criteria may be useful in differentiation of SVT types. Prediction of mechanism prior to EPS may provide additional benefits concerning the fluoroscopic exposure time and cardiac catheterization procedure.

Echocardiographic prediction of long-term response to biventricular pacemaker in severe heart failure.

BACKGROUND: Biventricular pacing substantially improves LV systolic function and symptom status in some patients with dilated cardiomyopathy. AIMS: To assess whether the long-term benefit could be predicted from the echocardiographic parameters. METHODS AND RESULTS: Sixteen patients with dilated cardiomyopathy who underwent atrio-biventricular pacemaker implantation were analyzed in two groups: the responders (n=11) were those with a symptomatic improvement of one or more NYHA functional class; the non-responders (n=5) failed to improve at follow-up (7.6+/-5 months). Echocardiography was performed at baseline, the day after the implantation and then every 3 months. Besides the conventional parameters, the following variables were included: LV diastolic filling time (DFT); the duration of mitral regurgitation (dMR); and LV dP/dt obtained from the continuous wave mitral regurgitation curve. While the baseline DFT and dP/dt were not significantly different between non-responders and responders (256+/-105 vs. 358+/-115, P=0.14 and 564+/-199 vs. 468+/-117, P=0.44, respectively), the QRS width (149+/-15 vs. 175+/-24 ms, P=0.05) and the dMR (343+/-70 vs. 443+/-49 ms, P=0.007) were higher in the responders. The changes of dMR, DFT and QRS width by pacing were not significantly different between groups (P=0.18, 0.30 and 0.77, respectively). However, the change of LV dP/dt by pacing in the responders was significantly different than for non-responders (from 468+/-117 to 676+/-216 mmHg/s vs. from 564+/-199 to 483+/-94, P=0.002). An acute increase in LV dP/dt over 22% by pacing yielded only two false negatives and no false positives in predicting the long-term responsiveness. CONCLUSION: Patients with longer QRS and dMR are more likely to benefit from atrio-biventricular stimulation. The acute changes of Doppler derived LV dP/dt may provide valuable information in predicting the long-term response to biventricular pacing.

Long-term follow-up of pacemakers with an Autocapture pacing system.

UNLABELLED: The aim of this study was to evaluate the safety and performance of the Autocapture pacing system during a 5-year follow-up period. The study was conducted retrospectively between May 1996 and May 2001. Sixty consecutive patients who had undergone VVI pacemaker implantation using an Autocapture program with leads 1402T (n: 31) and 1452T (n: 29) were included in the study. Intraoperative measurements including a ventricular stimulation threshold test, sensing of intrinsic R wave (mV), and lead impedance (W) were done by a standard pacing system analyzer. Evoked responses (ER, mV) and polarization signals (PS, mV) were measured after the pocket was closed. Pacing thresholds by Autocapture (AC thrd, V) and Vario (Vario thrd, V), battery current (mA), and battery impedance (kW) were also repeated during predischarge and 1, 6, 12, 18, 24, 30, 40, 50, and 60 months after discharge. According to the ER and PS values an Autocapture algorithm could be activated in 49 patients (88%). The Autocapture algorithm remained active during the follow-up in all of these patients. In patients with inappropriate ER and PS values (11 patients, 12%), pacemakers were programmed to a VVIR pacing mode and Autocapture algorithm was inactivated. ER and PS values did not reach appropriate values to activate the Autocapture algorithm in any of these patients in consecutive follow-ups. Twenty-four-hour Holter monitoring could be conducted in 32 patients (53%). In all recordings, when the loss of capture occurred, it was confirmed that back-up pacing continued. When the first measurements recorded during implantation were compared to approximately the 5th year measurements; ER (9.2 mV vs 9.6 mV), PS signal (1.13 +/- 0.30 mV vs 1.15 +/- 0.72 mV), AC thrd (0.4 V vs 1.2 V), Vario thrd (0.7 V vs 1.3 V), and lead impedance (502 ohm vs 620 ohm) were not changed significantly. Battery impedance increased 1 kOhm between 30-40 months of the implantation. Seven deaths occurred during follow-up. Three patients had fatal myocardial infarction, one died due to a non-cardiac event, and the remaining three died due to progressive heart failure. CONCLUSION: ER, R wave amplitude, and PS, which are the main parameters for the continuation of Autocapture function, did not change significantly during long-term follow-up. High output back up pacing provided additional safety for sudden rises in threshold. The Autocapture pacing algorithm was found to be effective and reliable during long-term follow-up.