Biomedical subjects

Henrik Egeblad

Publications and source records attributed to Henrik Egeblad.

9 recordsLinked to original sources

PubMed2003

Doppler tissue imaging reveals systolic dysfunction in patients with hypertension and apparent "isolated" diastolic dysfunction.

The purpose of this study was to examine left ventricular systolic longitudinal contraction in patients with essential hypertension with normal ejection fraction and fractional shortening. We used tissue tracking and strain rate Doppler echocardiography to evaluate left ventricular longitudinal contraction in 40 patients with hypertension and 30 age-matched control patients. Tissue tracking and peak systolic strain rate were significantly decreased in patients with hypertension and diastolic dysfunction compared with patients with hypertension and normal diastolic function or with control patients. In conclusion, patients with hypertension who, earlier, were considered to have isolated diastolic dysfunction were demonstrated to have reduced left ventricular systolic longitudinal function.

Case-Control Studies↗

PubMed2002

Sequential versus simultaneous biventricular resynchronization for severe heart failure: evaluation by tissue Doppler imaging.

BACKGROUND: Cardiac resynchronization therapy (CRT) by means of simultaneous biventricular pacing improves left ventricular systolic performance and synchrony in patients with heart failure and bundle-branch block. We used tissue tracking and 3D echocardiography to evaluate the impact of sequential CRT with individualized interventricular delay programming. METHODS AND RESULTS: Twenty consecutive patients with severe heart failure and left bundle-branch block were included. Tissue tracking and 3D echocardiography were carried out before and on the day after pacemaker implantation. Eleven different interventricular delays were examined in each patient. Patients were reexamined after 3 months. Simultaneous CRT immediately reduced the extent of myocardium displaying delayed longitudinal contraction (DLC) from 48.6+/-16% to 23.2+/-13% (P<0.01) and increased left ventricular ejection fraction percentage (LVEF%) from 22.4+/-6% to 29.7+/-5% (P<0.01). However, optimum sequential CRT caused a further reduction in the extent of DLC from 23.2+/-13% to 11.1+/-7.2% (P<0.01), with a simultaneous increase in LVEF% (from 29.7+/-5% to 33.9+/-6%, P<0.01). Three months of optimum sequential CRT further improved LVEF% (from 33.6+/-6% to 38.6+/-7.2%, P<0.01). Tissue tracking detected the segments with DLC, and their location determined optimum interventricular delay programming. Compared with simultaneous CRT, sequential CRT increased diastolic filling time by 7+/-2.5%. CONCLUSIONS: Compared with simultaneous CRT, sequential CRT significantly improves left ventricular systolic and diastolic performance. Tissue tracking can be used to select optimum interventricular delay during CRT.

Aged↗

PubMed2002

Tissue Doppler imaging predicts improved systolic performance and reversed left ventricular remodeling during long-term cardiac resynchronization therapy.

OBJECTIVES: We sought to evaluate the long-term impact of cardiac resynchronization therapy (CRT) on left ventricular (LV) performance and remodeling using three-dimensional echocardiography and tissue Doppler imaging (TDI). BACKGROUND: Three-dimensional echocardiography and TDI allow rapid and accurate evaluation of LV volumes and performance. METHODS: Twenty-five consecutive patients with severe heart failure and bundle branch block who underwent biventricular pacemaker implantation were included. Before and after implantation of the pacemaker, three-dimensional echocardiography and TDI were performed. These examinations were repeated at outpatient visits every six months. RESULTS: Five patients (20%) died during one-year follow-up. In the remaining 20 patients, significant reductions in LV end-diastolic volume and LV end-systolic volume of 9.6 +/- 14% and 16.5 +/- 15%, respectively (p < 0.01), could be demonstrated during long-term follow-up. Accordingly, LV ejection fraction increased by 21.7 +/- 18% (p < 0.01). According to a newly developed TDI technique-tissue tracking-all regional myocardial segments improved their longitudinal systolic shortening (p < 0.01). The extent of the LV base displaying delayed longitudinal contraction, as detected by TDI before pacemaker implantation, predicted long-term efficacy of CRT. The QRS duration failed to predict resynchronization efficacy. CONCLUSIONS: Cardiac resynchronization significantly improved LV function and reversed LV remodeling during long-term follow-up. Patients likely to benefit from CRT can be identified by TDI before implantation of a biventricular pacemaker.

Bundle-Branch Block↗

PubMed2002

Impact of daily life myocardial ischemia in patients with chronic reversible and irreversible myocardial dysfunction.

Repetitive myocardial ischemia during daily life has been suggested as the underlying mechanism of reversible myocardial dysfunction, which may progress into a hibernating state. Thirty-seven patients with ischemic cardiomyopathy (ejection fraction 35 +/- 7%) underwent positron emission tomography (N-13 ammonia and 18-F-fluoro-2-deoxy-glucose [FDG]) and exercise testing before coronary artery bypass grafting (CABG) and 48- hour ambulatory electrocardiographic monitoring to detect ischemia before CABG and 6 months postoperatively. Reversibility of regional myocardial dysfunction was detected by echocardiographic follow-up at 5 days, 2 months, and 6 months after the operation. Preoperatively, ischemic episodes during daily activities were more common (2 [25th to 75th percentiles 0 to 4] vs 0 episodes, p <0.01) and duration of ischemia longer (9 [25th to 75th percentiles 0 to 37] vs 0 [25th to 75th percentiles 0 to 1] minutes, p <0.02) in patients with reversible dysfunction (n = 15) than in patients with irreversible dysfunction (n = 22). The number of ischemic episodes per patient correlated with the numbers of reversibly dysfunctional segments (p = 0.003), viable segments as seen by positron emission tomography (p <0.05), and flow-metabolic mismatch segments (p <0.05). CABG eliminated ambulatory ischemic episodes in patients with reversible dysfunction (0 episodes, p <0.05 vs before CABG). Preoperatively, all patients with reversible dysfunction had a positive exercise test (14 of 15 patients), whereas daily life ischemia was present in 60% of patients. Reversibly dysfunctional segments in patients with ambulatory ischemia had faster recovery of function (15 of 28 patients vs 2 of 12 patients recovered at 5 days, p <0.05), higher FDG uptake (0.86 +/- 0.19% vs 0.71 +/- 0.24%, p <0.05) than in patients without ambulatory ischemia, whereas perfusion was similar (0.63 +/- 0.20 and 0.62 +/- 0.19 ml/g/min). Thus, exercise-induced myocardial ischemia is associated with reversibility of myocardial dysfunction, but not all patients with reversible ischemic cardiomyopathy have ischemic attacks during daily life.

Activities of Daily Living↗

PubMed2002

Coronary collaterals during single-vessel coronary angioplasty: effects of nitroglycerin.

BACKGROUND: Although the protective role of collaterals in coronary artery disease (CAD) is well known, the influence of drugs on collateral function remains controversial. HYPOTHESIS: We aimed to investigate prospectively the prevalence of spontaneously visible and recruitable coronary collaterals in consecutive patients with single-vessel CAD and the effect of systemic administration of nitroglycerin on these types of collaterals during percutaneous transluminal coronary angioplasty (PTCA). METHODS: Ipsi- and contralateral coronary artery contrast injections were performed before and during PTCA. Simultaneously with balloon occlusion, we measured coronary artery occlusion pressure via the balloon catheter. All measurements were repeated after administration of 0.5 mg of nitroglycerin intravenously. RESULTS: Of 101 consecutive patients, 24% had spontaneously visible and 30% had recruitable collaterals. Contralateral collaterals were five times more frequent than ipsilateral collaterals. Presence of collaterals was highly associated with the degree of coronary stenosis. Coronary occlusion pressure was higher in patients with than in those without collaterals. Collaterals prevented pain and ischemia during PTCA, and in this respect spontaneously visible collaterals were more effective than recruitable collaterals. There was no effect of systemic administration of nitroglycerin on appearance or occlusion pressure of coronary collaterals. CONCLUSION: Coronary collaterals were found in more than half of patients with single-vessel CAD, as the prevalence of recruitable collaterals was slightly higher than that of spontaneously visible collaterals. Nitroglycerin did neither recruit nor augment coronary collaterals.

Adult↗

PubMed2002

Intraventricular dispersion and temporal delay of early left ventricular filling after acute myocardial infarction. Assessment by magnetic resonance velocity mapping.

This article aims to describe early left ventricular diastolic inflow using magnetic resonance velocity mapping in patients with recent acute myocardial infarction and in normal volunteers. Magnetic resonance velocity mapping was performed in a long axis plane through the hearts of 46 patients with recent, first time acute myocardial infarction and 43 age-matched normal volunteers. The peak velocities at six levels of the early diastolic inflow stream were recorded. A velocity index was calculated as the peak velocity in each position relative to the peak velocity at the mitral leaflet tips. Also, the temporal delay of velocity propagation was computed. Velocity index 4 cm downstream of mitral leaflet tips was lower in the acute myocardial infarction group (0.42 (0.17)) (mean (SD)) compared to controls (0.59 (0.25)) (p < 0.001). Temporal delay in the same position was longer in the acute myocardial infarction group (62 (67) ms) than in controls (32 (39) ms) (p < 0.02). Blood flow patterns in patients after acute myocardial infarction were characterized by increased dispersion of velocities and increased temporal delay of velocity propagation, probably reflecting impaired active left ventricular relaxation. Intraventricular flow measurements constitute a promising new technique for non-invasive assessment of left ventricular diastolic function.

Adult↗

PubMed2002

Coronary artery bypass surgery in heart failure patients with chronic reversible and irreversible myocardial dysfunction: effect on heart rate variability.

It is unknown whether surgical revascularization of viable and chronic reversibly dysfunctional myocardium in patients with heart failure is associated with a favorable effect on the autonomic control of heart rate. We studied 38 coronary artery bypass surgery (CABG) patients with an ejection fraction of 36 +/- 7%. Before CABG, the patients underwent 48-hour ambulatory electrocardiographic monitoring to measure heart rate variability (HRV), echocardiography to assess left ventricular function, and positron emission tomography and low-dose dobutamine echocardiography to assess viability. Six months after CABG, ambulatory electrocardiographic monitoring and echocardiography were repeated to assess HRV and recovery of left ventricular function. In spite of viable myocardium and recovery of left ventricular function following CABG, HRV indices were reduced 6 months postoperatively. A potential prognostic benefit gained by revascularizing patients with viability may occur in spite of deteriorated autonomic control of heart rate.

Aged↗

PubMed1997

Echocardiographic Assessment of Regional and Global Left Ventricular Function Wall-Motion Scoring in Parasternal and Apical Views Versus Apical Views Alone.

The aim of the study was to examine the value of echocardiographic wall-motion scoring in apical views as compared to a conventional combination of apical and parasternal views. In 50 consecutive patients referred to coronary arteriography for potential revascularization, echocardiographic digital image loops of the left ventricle (LV) were recorded in parasternal long- and short-axis views and in apical long-axis, two-, and four-chamber views. Eight of 16 standardized LV segments appear both in the apical and in the parasternal views (group 1 segments). The remaining eight segments are visualized in the apical views only (group 2). Using a cross-over design, two cardiologists independently performed regional wall-motion scoring based on apical views, respectively, based on the combination of parasternal and apical views. Using the conventional approach (parasternal and apical views) 98% of the total 800 segments were scored as compared to 95% when using the mere apical approach (P < 0.05); 94% of the 800 segments were scored from both approaches. The regional wall-motion score was identical in 76% of group 1 segments and in 77% of group 2 segments. It diverged, at most, one score in 94% of group 1 segments and in 91% of group 2 segments (P > 0.05). LV ejection fraction (EF) calculated on the basis of average wall-motion score exclusively assessed from the apex differed little from angiographic EF (mean difference 2.0%, 95% confidence limits +/- 6.6%). Intraobserver variability of wall-motion scores (n = 25 patients) was small and almost identical for the two cardiologists. Similarly, interobserver variability was small and identical for apical views and conventional views. We conclude that there is no substantial loss of information when echocardiographic evaluation of regional and global left ventricular function is performed solely from the apical approach.

Journal Article↗

PubMed1996

Rupture of Aortic Dissection During Attempted Transesophageal Echocardiography.

Transesophageal echocardiography (TEE) provides a rapid and accurate diagnosis in patients with dissection of the thoracic aorta. The procedure is considered to be safe. We report a case where rupture of a dissecting thoracic aneurysm occurred during attempted TEE in a patient, who had been clinically stable for 1 week. TEE was performed because aortic valve endocarditis was suspected, and the procedure did not include close surveillance of the blood pressure. Careful manipulation of the probe, adequate sedation, monitoring, and treatment of acute rises in blood pressure was recommended in patients with even a slight suspicion of dissection undergoing TEE. (ECHOCARDIOGRAPHY, Volume 13, July 1996)

Journal Article↗