Biomedical subjects
Pekka Raatikainen
Publications and source records attributed to Pekka Raatikainen.
Prevalence, characteristics and natural course of inappropriate sinus tachycardia.
AIMS: To study the prevalence, characteristics and natural course of inappropriate sinus tachycardia (IST). METHODS AND RESULTS: The prevalence and characteristics of IST were evaluated in a random sample of 604 middle-aged subjects. Seven of the subjects (1.16%) fulfilled the contemporary diagnostic criteria of IST. The systolic (147+/-11 mmHg vs. 130+/-13 mmHg, P<0.001) and diastolic ambulatory blood pressures (92+/-7 mmHg vs. 81+/-8 mmHg, P<0.001) were higher among the subjects with IST than among the controls. The other laboratory, echocardiographic and personality measurements, with the exception of the hostility score (10+/-2 vs. 8+/-3, P<0.001), revealed no differences between the groups. The natural course and prognosis of the disorder was assessed among the subjects fulfilling the IST criteria and nine previously diagnosed IST patients. During a mean follow-up of 6.0+/-2.4 years, none of the subjects developed any clinical or echocardiographic evidence of structural heart disease despite ongoing palpitations, and there was no significant reduction in the 24-h average HR (9+/-2 bpm vs. 89+/-8 bpm, P=0.204). CONCLUSION: The prevalence of IST in a middle-aged population was higher than previously assumed. Despite the chronic nature of the disorder, the prognosis of IST was benign. The causal relationship between IST and hypertension and/or hostile personality type remains speculative.
Prediction of sudden cardiac death after myocardial infarction in the beta-blocking era.
OBJECTIVES: This study assessed the predictive power of arrhythmia risk markers after an acute myocardial infarction (AMI). BACKGROUND: Several risk variables have been suggested to predict the occurrence of sudden cardiac death (SCD), but the utility of these variables has not been well established among patients using medical therapy according to contemporary guidelines. METHODS: A consecutive series of 700 patients with AMI was studied. The end points were total mortality, SCD, and nonsudden cardiac death (non-SCD). Nonsustained ventricular tachycardia (nsVT), ejection fraction (EF), heart rate variability, baroreflex sensitivity, signal-averaged electrocardiogram (SAECG), QT dispersion, and QRS duration were analyzed (n = 675). Beta-blocking therapy was used by 97% of the patients at discharge and by 95% at one and two years after AMI. RESULTS: During a mean (+/-SD) follow-up of 43 +/- 15 months, 37 non-SCDs (5.5%) and 22 SCDs (3.2%) occurred. All arrhythmia risk variables differed between the survivors and those with non-SCD (e.g., the standard deviation of N-N intervals was 98 +/- 32 vs. 74 +/- 21 ms [p < 0.001] and the QRS duration was 103 +/- 22 vs.89 +/- 16 ms [p < 0.001]). Sudden cardiac death was weakly predicted only by reduced EF (<0.40; p < 0.05), nsVT (p < 0.05), and abnormal SAECG (p < 0.05), but not by autonomic markers or standard ECG variables. The positive predictive accuracy of EF, nsVT, and abnormal SAECG as predictors of SCD was relatively low (8%, 12%, and 13%, respectively). CONCLUSIONS: The common arrhythmia risk variables, particularly the autonomic and standard ECG markers, have limited predictive power in identifying patients at risk of SCD after AMI in the beta-blocking era.