Aims: Increased spatial angle between QRS complex and T wave loop orientations has repeatedly been shown to predict cardiac risk. However, there is no consensus on the methods for the calculation of the angle. This study compared the reproducibility and predictive power of three most common ways of QRS-T angle assessment. Methods and results: Electrocardiograms of 352 healthy subjects, 941 survivors of acute myocardial infarction (MI), and 605 patients recorded prior to the implantation of automatic defibrillator [implantable cardioverter defibrillator (ICD)] were used to obtain QRS-T angle measurements by the maximum R to T (MRT), area R to T (ART), and total cosine R to T (TCRT) methods. The results were compared in terms of physiologic reproducibility and power to predict mortality in the cardiac patients during 5-year follow-up. Maximum R to T results were significantly less reproducible compared to the other two methods. Among both survivors of acute MI and ICD recipients, TCRT method was statistically significantly more powerful in predicting mortality during follow-up. Among the acute MI survivors, increased spatial QRS-T angle (TCRT assessment) was particularly powerful in predicting sudden cardiac death with the area under the receiver operator characteristic of 78% (90% confidence interval 63-90%). Among the ICD recipients, TCRT also predicted mortality significantly among patients with prolonged QRS complex duration when the spatial orientation of the QRS complex is poorly defined. Conclusion: The TCRT method for the assessment of spatial QRS-T angle appears to offer important advantages in comparison to other methods of measurement. This approach should be included in future clinical studies of the QRS-T angle. The TCRT method might also be a reasonable candidate for the standardization of the QRS-T angle assessment.

• MeSH
• Action Potentials * MeSH
• Defibrillators, Implantable MeSH
• Adult MeSH
• Electric Countershock instrumentation   MeSH
• Electrocardiography * standards   MeSH
• Risk Assessment MeSH
• Myocardial Infarction diagnosis   mortality   physiopathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Death, Sudden, Cardiac epidemiology   MeSH
• Predictive Value of Tests MeSH
• Prognosis MeSH
• Reproducibility of Results MeSH
• Risk Factors MeSH
• Aged MeSH
• Arrhythmias, Cardiac diagnosis   mortality   physiopathology   surgery   MeSH
• Heart Rate * MeSH
• Case-Control Studies MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

Cíl: Cílem práce bylo posoudit prognostický význam koronárního kalciového skóre v kombinaci se zátěžovým zobrazením myokardu pomocí jednofotonové emisní tomografi e (SPECT) u asymptomatických rizikových pacientů. Metodika: Byl analyzován soubor 128 pacientů (79 mužů a 49 žen, průměrný věk 54 ± 10 let, 25 s diabetem), kteří prodělali zátěžové gated SPECT vyšetření a současně kvantifi kaci kalciového skóre. Sumační perfuzní zátěžové a rozdílové skóre (SSS, resp. SDS), ejekční frakce (EF) a end-diastolické, resp. end-systolické objemy levé komory (EDV/ESV) byly automaticky stanoveny programem 4D-MSPECT. Závažná kardiální příhoda byla defi nována jako náhlá srdeční smrt nebo nefatální infarkt myokardu (IM), a dále byly evidovány obtíže vyžadující revaskularizaci. Výsledky: Během průměrného sledovacího období 17 ± 9 měsíců jsme evidovali dva nefatální IM a osm revaskularizací. V podskupině 10 pacientů s kardiální příhodou byla v porovnání s pacienty bez příhody horší perfuze (SSS 10 ± 12 vs. 1 ± 0 a SDS 6 ± 9 vs. 0 ± 1; p < 0,05), funkce levé komory (pozátěžová EF 56 ± 12 % vs. 68 ± 9 %, klidová EF 56 ± 7 % vs. 66 ± 9 %, pozátěžové EDV/ESV 129 ml/59 ml vs. 98 ml/34 ml; p < 0,05) a vyšší kalciové skóre (588 ± 1475 vs. 78 ± 136; p < 0,05). Roční incidence kardiálních příhod narůstala s hodnotou kalciového skóre (2,5 %, 6,1 %, 11,1 % a 14,8 % pro kalciové skóre 0–10, 11–100, 101–400 a > 400). Žádná kardiální příhoda nebyla zaznamenána u 20 z 27 asymptomatických pacientů, kteří měli kalciové skóre ≥ 101 a současně normální SPECT. Závěr: Stanovení kalciového skóre v kombinaci se zátěžovým SPECT zobrazením myokardu umožňuje posoudit prognózu asymptomatických rizikových pacientů.

Aim: The aim of this study was to investigate the prognostic value of coronary artery calcium (CAC) score in combination with cardiac stress sigle-photon emission tomography (SPECT) imaging in an asymptomatic population. Methods: One hundred twenty-eight consecutive asymptomatic patients (79 men, mean age 54±10 years, 25 with diabetes) underwent stress cardiac gated SPECT imaging and CT assessment of CAC score. Perfusion summed stress and diff erence score (SSS and SDS, resp.), the left ventricular ejection fraction (LVEF) and end-diastolic/end-systolic volumes (EDV/ESV) were automatically calculated using 4D-MSPECT. Cardiac event was defi ned as either cardiac death, nonfatal myocardial infarction (MI), or conditions requiring coronary revascularization. Results: During an average follow-up of 17±9 months, two patients had nonfatal MI, and revascularization was required in 8 patients. In the subgroup of 10 patients with cardiac events, the observed parameters was signifi cantly worse than in patients without cardiac event concerning perfusion (SSS 10±12 vs. 1±0 and SDS 6±9 vs. 0±1, P<0.05), the left ventricular function (stress LVEF 56±12% vs. 68±9%, rest LVEF 56±7% vs. 66%±9, stress EDV/ESV 129 ml/59 ml vs. 98 ml/34 ml, P<0.05), and CAC score (588±1475 vs. 78±136, P<0.05). An annual cardiac event rate depended on the amount of CAC (2.5%, 6.1%, 11.1%, and 14.8% for CAC score 0–10, 11–100, 101–400, and >400, resp.). Moderate and high risk CAC score (101–400 and >400, resp.) was detected in 27 patients; however, no cardiac event was observed in 20 of them who had CAC ≥101 and simultaneously normal stress gated SPECT. Conclusion: CAC scoring combined with cardiac gated SPECT enables evaluation of prognosis in asymptomatic risk individuals.

• Keywords
• gated SPECT myokardu, koronární kalciové skóre, stratifikace rizika,
• MeSH
• Financing, Organized MeSH
• Risk Assessment MeSH
• Myocardial Infarction epidemiology   MeSH
• Myocardial Ischemia epidemiology   pathology   MeSH
• Tomography, Emission-Computed, Single-Photon methods   MeSH
• Calcinosis classification   MeSH
• Ventricular Dysfunction MeSH
• Humans MeSH
• Death, Sudden, Cardiac epidemiology   MeSH
• Coronary Artery Disease epidemiology   etiology   MeSH
• Predictive Value of Tests MeSH
• Prognosis MeSH
• Risk Factors MeSH
• Technetium Tc 99m Sestamibi diagnostic use   MeSH
• Exercise Test methods   utilization   MeSH
• Check Tag
• Humans MeSH

The study was designed to develop a simple risk stratification score for primary therapy with an implantable cardioverter-defibrillator (ICD). BACKGROUND: Current guidelines recommend primary ICD therapy in patients with a low ejection fraction (EF). However, the benefit of the ICD in the low EF population may not be uniform. METHODS: Best-subset proportional-hazards regression analysis was used to develop a simple clinical risk score for the end point of all-cause mortality in patients allocated to the conventional therapy arm of MADIT (Multicenter Automatic Defibrillator Implantation Trial)-II after excluding a pre-specified subgroup of very high-risk (VHR) patients (defined by blood urea nitrogen [BUN] >or=50 mg/dl and/or serum creatinine >or=2.5 mg/dl). The benefit of the ICD was then assessed within risk score categories and separately in VHR patients. RESULTS: The selected risk score model comprised 5 clinical factors (New York Heart Association functional class >II, age >70 years, BUN >26 mg/dl, QRS duration >0.12 s, and atrial fibrillation). Crude mortality rates in the conventional group were 8% and 28% in patients with 0 and >or=1 risk factors, respectively, and 43% in VHR patients. Defibrillator therapy was associated with a 49% reduction in the risk of death (p < 0.001) among patients with >or=1 risk factors (n = 786), whereas no ICD benefit was identified in patients with 0 risk factors (n = 345; hazard ratio 0.96; p = 0.91) and in VHR patients (n = 60; hazard ratio 1.00; p > 0.99). CONCLUSIONS: Our data suggest a U-shaped pattern for ICD efficacy in the low-EF population, with pronounced benefit in intermediate-risk patients and attenuated efficacy in lower- and higher-risk subsets.

• MeSH
• Defibrillators, Implantable MeSH
• Ventricular Dysfunction, Left etiology   mortality   therapy   MeSH
• Risk Assessment methods   MeSH
• Outcome Assessment, Health Care MeSH
• Myocardial Infarction complications   therapy   MeSH
• Kaplan-Meier Estimate MeSH
• Middle Aged MeSH
• Humans MeSH
• Death, Sudden, Cardiac epidemiology   prevention & control   MeSH
• Proportional Hazards Models MeSH
• Aged MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH

This study sought to identify the incidence and outcome related to inappropriate implantable cardioverter-defibrillator (ICD) shocks, that is, those for nonventricular arrhythmias. BACKGROUND: The MADIT (Multicenter Automatic Defibrillator Implantation Trial) II showed that prophylactic ICD implantation improves survival in post-myocardial infarction patients with reduced ejection fraction. Inappropriate ICD shocks are common adverse consequences that may impair quality of life. METHODS: Stored ICD electrograms from all shock episodes were adjudicated centrally. An inappropriate shock episode was defined as an episode during which 1 or more inappropriate shocks occurred; another inappropriate ICD episode occurring within 5 min was not counted. Programmed parameters for patients with and without inappropriate shocks were compared. RESULTS: One or more inappropriate shocks occurred in 83 (11.5%) of the 719 MADIT II ICD patients. Inappropriate shock episodes constituted 184 of the 590 total shock episodes (31.2%). Smoking, prior atrial fibrillation, diastolic hypertension, and antecedent appropriate shock predicted inappropriate shock occurrence. Atrial fibrillation was the most common trigger for inappropriate shock (44%), followed by supraventricular tachycardia (36%), and then abnormal sensing (20%). The stability detection algorithm was programmed less frequently in patients receiving inappropriate shocks (17% vs. 36%, p = 0.030), whereas other programming parameters did not differ significantly from those without inappropriate shocks. Importantly, patients with inappropriate shocks had a greater likelihood of all-cause mortality in follow-up (hazard ratio 2.29, p = 0.025). CONCLUSIONS: Inappropriate ICD shocks occurred commonly in the MADIT II study, and were associated with increased risk of all-cause mortality.

• MeSH
• Defibrillators, Implantable adverse effects   MeSH
• Electric Countershock mortality   statistics & numerical data   adverse effects   MeSH
• Atrial Flutter mortality   therapy   MeSH
• Incidence MeSH
• Myocardial Infarction complications   physiopathology   MeSH
• Clinical Trials as Topic MeSH
• Middle Aged MeSH
• Humans MeSH
• Odds Ratio MeSH
• Prospective Studies MeSH
• Retrospective Studies MeSH
• Risk Factors MeSH
• Equipment Failure MeSH
• Tachycardia, Supraventricular mortality   therapy   MeSH
• Stroke Volume MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH