Accuracy and long-term prognostic value of pacing stress echocardiography compared with dipyridamole tl201 emission computed tomography in patients with a permanent pacemaker and known or suspected coronary artery disease.

OBJECTIVES: Myocardial ischemia is difficult to assess by noninvasive methods in patients with a permanent pacemaker. Pacing stress echocardiography (PASE) has been used successfully in the detection of coronary artery disease (CAD). However, there are no data comparing PASE and other methods. METHODS: We compared agreement and accuracy of PASE and radionuclide tomography (SPECT) in detecting CAD in 58 patients, mean age 75 +/- 7 years, with a permanent pacemaker and known or suspected CAD. Thirty-nine patients underwent coronary angiography. The prognostic value of these tests was determined by prediction of cardiac events and cardiac death. RESULTS: PASE and SPECT were positive in 39 and 43 patients, respectively. The agreement between the tests was 75%; kappa value 0.64. The sensitivity was 87 and 96% and the specificity 78 and 57%, respectively. With median follow-up of 51 months, there were 24 cardiac events and 8 cardiac deaths. Multivariable analysis determined that positive PASE was the only independent predictive factor associated with cardiac events and cardiac death. CONCLUSIONS: PASE is a feasible and effective method for detection of significant CAD in patients with permanent-pacemaker and allows effective risk stratification. PASE merits further study in larger prospective comparative studies.

Head-up tilt table testing in syncope: safety and efficiency of isosorbide versus isoproterenol in pediatric population.

BACKGROUND: The aim of this study was to compare the diagnostic value and safety of sublingual isosorbid dinitrate (ISDN) with intravenous isoproterenol (ISOP) during head-up tilt table testing (HUTT) in pediatric patients with suspected neurocardiogenic syncope. METHODS: One hundred thirty-six consecutive pediatric patients complaining of presyncope or syncope were submitted to HUTT for the first time. Those who did not develop syncope or presyncope during passive HUTT for 20 minutes underwent repeated HUTT with either 1.25 to 2.5 mg sublingual ISDN or intravenous ISOP (1-3 mug/min) for 20 minutes. There were 54 boys and 82 girls, aged 10 to 18 years with an average of 15.5 +/- 2.4 years and a median of 16 years. Among the patients with cardioinhibition or mixed responses, the severity of the bradyarrhythmia was scored 1 to 3 (restoration of effective rhythm within 10 seconds, 10-20 seconds, and >20 seconds while back to supine position, respectively). RESULTS: During the passive period, 24 (17.6%) of 136 patients had a positive response to HUTT. Syncope was observed in another 44 patients during either ISDN or ISOP period (14/58 [24.1%] and 30/54 [55.5%] with ISDN vs ISOP, respectively, P < .05). The time to symptoms was shorter with both ISDN and ISOP compared with passive period (6.5 +/- 2.9, 6.3 +/- 5.9, and 10.3 +/- 4.4, minutes, respectively, P < .05). The severity score for cardioinhibition response was significantly higher with ISDN compared with the passive period and ISOP (2 +/- 0.8, 1.25 +/- 0.45, and 1.26 +/- 0.45, respectively, P < .01). CONCLUSIONS: Sublingual ISDN is less sensitive and less safe compared to intravenous ISOP in assessing pediatric age patients with suspected neurocardiogenic syncope and with a negative result in tilt test without provocation. The simplicity of ISDN use should be weighed against the risk of longer symptoms with ISDN.

Implantable cardioverter defibrillators in Israel: utilization and implantation trends.

BACKGROUND: Since its introduction, the implantable cardioverter defibrillator (ICD) has evolved to its present status as the dominant therapeutic modality for patients with life-threatening arrhythmias. Several randomized studies have shown the benefit of ICD implantation as the first choice of treatment for primary as well as secondary indications for ventricular arrhythmias. Therefore, it is expected that the use of ICDs will increase further. The main objectives of this study were to analyze the Israeli experience with ICD implantation from 1993 to 1999, to examine the diffusion of ICD therapy in Israel and the evolution of implantation patterns and indications. METHODS: We conducted a retrospective review and analysis of an ICD registry for the period of January 1993-December 1999. Data collected included demographic, administrative, clinical and survival data. RESULTS: A total of 732 new implantations were identified and reviewed. The mean length of follow up of all patients was 30.7+/-21.1 months. 86% of patients were males and the mean age at implantation was 62.6+/-12.4 years. 79% of patients had CAD and the mean EF of all patients was 29.2+/-11.2%. 135 patients (18.4%) died during follow-up. One, two and three-year survival rates were calculated and were 92.7%, 87.8% and 82.0% respectively. A steady increase in implantation rate and in implanting centers was observed over the years. CONCLUSIONS: ICD therapy is relatively expensive; therefore a national registry which is continuously monitored may be the most expedient method to follow clinical and economic aspects of the utilization of this therapeutic modality.