Roman Panovský

Variability of Phase Shift Between Blood Pressure and Heart Rate Fluctuations A Marker of Short-Term Circulation Control

Background We postulated that the variability of the phase shift between blood pressure and heart rate fluctuation near the frequency of 0.10 Hz might be useful in assessing autonomic circulatory control. Methods and Results We tested this hypothesis in 4 groups of subjects: 28 young, healthy individuals; 13 elderly healthy individuals; 25 patients with coronary heart disease; and 19 patients with a planned or implanted cardioverterdefibrillator (ICD recipients). Data from 5 minutes of free breathing and at 2 different, controlled breathing frequencies (0.10 and 0.33 Hz) were used. Clear differences (P<0.001) in variability of phase were evident between the ICD recipients and all other groups. Furthermore, at a breathing frequency of 0.10 Hz, differences in baroreflex sensitivity (P<0.01) also became evident, even though these differences were not apparent at the 0.33‐Hz breathing frequency. Conclusions—The frequency of 0.10 Hz represents a useful and potentially important one for controlled breathing, at which differences in blood pressure‐RR interactions become evident. These interactions, whether computed as a variability of phase to define stability of the blood pressure‐heart rate interaction or defined as the baroreflex sensitivity to define the gain in heart rate response to blood pressure changes, are significantly different in patients at risk for sudden arrhythmic death. In young versus older healthy individuals, only baroreflex gain is different, with the variability of phase being similar in both groups. These measurements of short‐term circulatory control might help in risk stratification for sudden cardiac death. (Circulation. 2003;108:292‐297.)

Prognosis of patients with chronic coronary artery disease and severe left ventricular dysfunction. The importance of myocardial viability

The choice of optimal treatment strategy in patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction is often difficult. The aim of this study was to compare long‐term results of patients with chronic CAD, severe heart failure and a defined scope of myocardial viability treated with coronary revascularization, heart transplantation, or kept on medical therapy.

Association of coronary artery disease, erectile dysfunction,and endothelial nitric oxide synthase polymorphisms

The purpose of this study was to determine the relationship between erectile dysfunction (ED), coronary artery disease (CAD), and T−786C and intron 4 a/b endothelial nitric oxide synthase (eNOS) polymorphisms in 419 patients with suspected or known CAD referred for coronary angiography. The patients had a high prevalence of risk factors for both CAD and ED: hypercholesterolemia (64%), hypertension (74%), diabetes mellitus (25%), obesity (30%), and smoking (63%). Three hundred and twenty-one patients had significant coronary atherosclerosis (luminal diameter narrowing of 50% or more of at least 1 coronary artery), 41 had insignificant coronary stenoses, and 57 patients were found to have coronary arteries without the evidence of atherosclerosis. The prevalence of ED in these groups was 79%, 76%, and 67% (P = NS), respectively. As compared to patients without ED, those with ED exhibited significantly higher probability of having significant coronary atherosclerosis (69% vs 79%, P = 0.04), higher number of significant coronary stenoses (median, 1 vs 2, P = 0.004), and a higher prevalence of a triple-vessel disease (12% vs 25%, P = 0.004). We did not find any relationship between T−786C and intron 4 a/b polymorphisms and the manifestation of coronary atherosclerosis or the presence of ED. In conclusion, in patients with numerous cardiovascular risk factors referred for coronary angiography, there was a high prevalence of ED in patients with both the presence and the absence of coronary atherosclerosis. The coincidence of CAD and ED identified patients at increased risk of severe forms of CAD.

The role of exercise echocardiography in the diagnostics of heart failure with normal left ventricular ejection fraction

AIMS Few data are available on the exercise-induced abnormalities of myocardial function in patients with exertional dyspnoea and normal left ventricular ejection fraction (LV EF). The main aims of this study were to determine the prevalence of isolated exercise-induced heart failure with normal ejection fraction (HFNEF) and to assess whether disturbances in LV or right ventricular longitudinal systolic function are associated with the diagnosis of HFNEF. METHODS AND RESULTS Eighty-four patients with exertional dyspnoea and normal LV EF and 14 healthy controls underwent spirometry, NT-proBNP plasma analysis, and exercise echocardiography. Doppler LV inflow and tissue mitral and tricuspid annular velocities were analysed at rest and immediately after the termination of exercise. Of the 30 patients with the evidence of HFNEF, 6 (20%) patients had only isolated exercise-induced HFNEF. When compared with the remaining patients, those with HFNEF had a significantly lower resting and exercise peak mitral annular systolic velocity (Sa) and the mitral annular velocity during atrial contraction, lower exercise peak mitral annular velocity at early diastole, and lower exercise peak systolic velocity of tricuspid annular motion. The multivariate logistic regression analysis including both parameters standardly defining HFNEF and the new Doppler variables potentially associated with the diagnosis of HFNEF revealed that NT-proBNP, LV mass index, left atrial volume index, and Sa significantly and independently predict the diagnosis of HFNEF. CONCLUSION A significant proportion of patients require exercise to diagnose HFNEF. Sa appears to be a significant independent predictor of HFNEF, which may increase the diagnostic value of models utilizing the variables recommended by the European Society of Cardiology guidelines.

Prognostic importance of the quantification of myocardial viability in revascularized patients with coronary artery disease and moderate-to-severe left ventricular dysfunction.

The aim of this study was to assess the prognostic value of the amount of dysfunctional but viable myocardium in revascularized patients with coronary artery disease and left ventricular dysfunction. To quantify the amount of dysfunctional but viable myocardium, low-dose dobutamine echocardiography was performed. The wall motion was scored using a 16-segment model. The dysfunctional segments were defined as viable if they exhibited functional improvement of at least 1 grade with any dose of dobutamine, or only worsening with dobutamine infusion. Two hundred and twenty patients were revascularized and followed-up for a mean period of 33+/-23 months (range, 0-86) for cardiac-related death and hospitalization for heart failure. Standard follow-up echocardiography was performed 3-6 months after revascularization. Receiver operating characteristic curve analysis identified six dysfunctional but viable segments as the optimal cutoff value for discriminating patients with and without risk of cardiac events. Thirty-eight patients exhibited a large amount of dysfunctional but viable myocardium (>or=6 segments, group A), 103 patients had a small amount of dysfunctional but viable myocardium (2-5 segments, group B), and 79 patients were found to have dysfunctional myocardium irreversibly damaged (group C). Similar baseline left ventricular ejection fractions of 36+/-4, 34+/-5, 35+/-5% in groups A, B, and C increased to 46+/-6% (P<0.01 versus baseline and versus groups B and C), to 39+/-5% (P<0.01 versus baseline and group C), and to 36+/-7% (P<0.01 versus baseline), respectively, after revascularization. The greatest functional improvement after revascularization in group A patients was accompanied by a lower frequency of cardiac events during follow-up (1 vs. 27 in group B, P<0.01, and versus 18 in group C, P<0.01) and by a better cardiac event-free survival according to Kaplan-Meier survival analysis (P<0.01 versus groups B and C, respectively). In conclusion, in revascularized patients with coronary artery disease and moderate-to-severe left ventricular dysfunction, the presence of >or=6 dysfunctional but viable segments identifies patients with the best prognosis.

The prognostic effect of different types of cardiac rehabilitation in patients with coronary artery disease.

AIM The purpose of this study was to access and compare the prognostic effects of different types of cardiac rehabilitation (CR) in patients with chronic coronary artery disease. METHODS One hundred fifty-two patients were retrospectively divided into 4 groups according to their adherence to physical activity recommendations. Patients in groups 1 and 2 participated in the guided 3-month exercise programme. Patients in group 1 then continued with individual exercise training, while patients in the group 2 stopped exercising after finishing the guide exercise programme. Patients in group 3 participated only in individual exercise training throughout the whole follow-up period, and patients in group 4 declined all exercise recommendations and did not exercise. The prognostic outcome of different types of cardiac rehabilitation was compared among the groups. In addition, patients who participated in individual exercise training according to recommendations (cohort IT+) were compared with patients who declined these activities (cohort IT-). RESULTS During a median follow-up of 94 months, 33 deaths occurred: 17 cardiovascular and 16 non-cardiac deaths. A Kaplan-Meier survival analysis demonstrated significantly better survival rates for patients who followed a long-term aerobic exercise training (IT+) than for those who did not participate or who had only a short-term exercise programme (IT-) (P = 0.009). CONCLUSION In our study, long-term exercise training had a higher impact on patient survival than short-term guided CR.

Long-term results of intracoronary bone marrow cell transplantation: the potential of gated sestamibi SPECT/FDG PET imaging to select patients with maximum benefit from cell therapy.

Purpose: This study assessed the effect of different levels of tracer uptake in the infarcted area on improvement of left ventricular function in patients treated by intracoronary mononuclear bone marrow cell (BMC) transplantation during long-term (12-month) follow-up. Methods: Thirty-seven patients with irreversible injury after their first acute myocardial infarction, as confirmed by dobutamine echocardiography and sestamibi single-photon emission computed tomography/fluorodeoxyglucose positron emission tomography underwent BMC transplantation (1 × 108 cells), whereas 36 similar patients were randomly assigned to a control group. Results: In 16 BMC-treated patients with very low sestamibi uptake (<30% of maximum) in the infarcted area, the mean baseline left ventricular ejection fraction (LVEF) increased at 3- and 12-month follow-up by 3% and 4% only, and mean end-diastolic/end-systolic volumes (EDV/ESV) enlarged by 20/7 mL and 23/9 mL, respectively (P = NS vs. controls). In 21 BMC-treated patients with higher sestamibi uptake (31%–50% of maximum), the LVEF improved by 6% and 7%, and EDV/ESV decreased by 4/13 mL and 1/13 mL, respectively (P < 0.05 vs. BMC-treated subgroup with low uptake and control subjects). There was no statistically significant difference in LVEF, EDV, or ESV changes between controls with low versus higher sestamibi uptake. Conclusion: During long-term follow-up, the post-transplant improvement of left ventricular function remained significant only in BMC-treated patients with higher sestamibi uptake.

Comparison of Acoustic Densitometry and Dobutamine Echocardiography for an Assessment of Myocardial Viability

Aim: The aim of this study has been to compare acoustic densitometry and dobutamine echocardiography for an assessment of myocardial viability. Methods and results: Thirty‐four patients with coronary artery disease and dysfunctional myocardial segments, who were referred for myocardial revascularization, underwent a viability assessment using low‐dose dobutamine echocardiography and acoustic densitometry. Results of the two techniques were compared to follow‐up resting echocardiography. This follow‐up examination was performed at a mean of 3 months after successful revascularization in order to assess the recovery of function in revascularized, initially dysfunctional segments. Echocardiography was performed in standard views using 16‐segment model of the left ventricle. Viable myocardium was identified by the augmentation of systolic thickening of an abnormal segment by at least one grade during dobutamine infusion and by the value of the maximal amplitude of cyclic variation of integrated backscatter. Acoustic densitometry had the sensitivity and specificity to predict functional recovery 90% and 77%, respectively. Dobutamine echocardiography had the sensitivity and specificity to predict contractile reserve 83% and 81%, respectively. The results were statistically comparable. Concordance between these methods was 80%. Conclusion: Acoustic densitometry and dobutamine echocardiography did not statistically differ in the prediction of functional recovery dysfunctional myocardial segments after revascularization.

The unique value of cardiovascular magnetic resonance in patients with suspected acute coronary syndrome and culprit-free coronary angiograms

BackgroundPatients with chest pain, elevated troponin, and unobstructed coronary disease present a clinical dilemma. The purpose of this study was to investigate the incremental diagnostic value of cardiovascular magnetic resonance (CMR) in a cohort of patients with suspected acute coronary syndrome (ACS) and unobstructed coronary arteries.ResultsData files of patients meeting the inclusion criteria in two cardiology centres were searched and analysed. The inclusion criteria included: 1) thoracic pain suspected with ACS; 2) a significant increase in the high-sensitive Troponin T value; 3) ECG changes; 4) coronary arteries without any significant stenosis; 5) a CMR examination included in the diagnostic process; 6) an uncertain diagnosis before the CMR exam; and 7) the absence of known CMR and contrast media contraindications. Special attention was paid to the benefits of CMR in determining the final diagnosis.In total, 136 patients who underwent coronary angiography for chest pain were analysed. The most frequent underlying causes were myocarditis (38%) and perimyocarditis (18%), followed by angiographically unrecognised acute myocardial infarction (18%) and Takotsubo cardiomyopathy (15%). The final diagnosis remained unclear in 6% of the patients. The contribution of CMR in determining the final diagnosis determination was crucial in 57% of the patients. In another 35% of the patients, CMR confirmed the suspicion and, only 8% of the CMR examinations did not help at all and had no influence on diagnosis or treatment.ConclusionCMR provided a powerful incremental diagnostic value in the cohort of patients with suspected ACS and unobstructed coronary arteries. CMR is highly recommended to be incorporated as an inalienable part of the diagnostic algorithms in these patients.

The Relation between eNOS -786 C/T, 4 a/b, MMP-13 rs640198 G/T, Eotaxin 426 C/T, -384 A/G, and 67 G/A Polymorphisms and Long-Term Outcome in Patients with Coronary Artery Disease.

Aim. The purpose of this study is to determine the association between eotaxin 426 C/T, −384 A/G, 67 G/A, eNOS −786 T/C, 4 a/b, and MMP-13 rs640198 G/T and prognosis of patients with known CAD. Methods. From total of 1161 patients referred to coronary angiography, 532 patients with angiographically confirmed CAD were selected. Their long-term outcome was followed up using hospital database. Subsequent events were assessed in this study: death or combined endpoint-myocardial infarction, unstable angina pectoris, revascularization, heart failure hospitalization, and cardioverter-defibrillator implantation. Results. The multivariate Cox regression model identified age, smoking, and 3-vessel disease as significant predictors of all-cause death. Further analysis showed that eotaxin 67 G/A (GA + AA versus GG) and eotaxin −384 A/G (GG versus GA + AA) were significant independent prognostic factors when added into the model: HR (95% CI) 2.81 (1.35–5.85), p = 0.006; HR (95% CI) 2.63 (1.19–5.83), p = 0.017; eotaxin −384 A/G was significantly associated with the event-free survival, but it did not provide the prognostic information above the effect of two- or three-vessel disease. Conclusion. The A allele in eotaxin 67 G/A polymorphism is associated with worse survival in CAD patients.