Lösse B

Doppler echocardiographic assessment of the pressure gradient during bicycle ergometry in hypertrophic cardiomyopathy

To assess the behavior of the subvalvular pressure gradient under physical exercise, 13 patients with obstructive hypertrophic cardiomyopathy were examined during upright bicycle ergometry by means of Doppler echocardiography. Additionally, right-sided cardiac catheterization was performed within 7 days. In 10 patients adequate Doppler tracings could be obtained during exercise. The Doppler-derived systolic pressure gradient increased from 75 +/- 24 to 140 +/- 42 mm Hg (p less than 0.0005). This was associated with an increase in the duration of the systolic mitral-septal contact from 59 +/- 21 to 136 +/- 28 ms (p less than 0.0005). Correlation between the pressure gradient and the duration of mitral-septal contact at rest and during exercise was good (r = 0.86), whereas correlation between the resting and exercise pressure gradient (r = 0.34) did not reach statistical significance. The increase in stroke volume during exercise, from 90 +/- 18 to 95 +/- 24 ml, was significant (p less than 0.05) but minimal. Therefore, only a moderate increase in systolic flow, from 205 +/- 54 to 268 +/- 78 ml/s (p less than 0.0005), was observed. Outflow tract resistance, defined as the ratio of the pressure gradient to systolic flow, increased from 0.38 +/- 0.11 to 0.57 +/- 0.24 mm Hg.s/ml (p less than 0.01). Thus, in a selected group of patients with hypertrophic cardiomyopathy a substantial increase in the maximal pressure gradient during upright bicycle ergometry was demonstrated in most patients. Exercise Doppler echocardiography may be valuable to assess the hemodynamic significance of obstruction in individual patients in a physiologic setting and has a potential to monitor the effect of therapeutic interventions.

Increased risk of bacterial endocarditis in inflammatory bowel disease

PURPOSE The purpose of this retrospective as well as prospective case-control study was to analyze a possible overrepresentation of inflammatory bowel diseases among patients with native valve endocarditis as well as the factors that predispose patients with inflammatory bowel disease to infective endocarditis. PATIENTS AND METHODS Among 213 consecutive patients treated for proven native valve endocarditis, six (2.8%) had inflammatory bowel diseases (three with ulcerative colitis and three with Crohns disease). Three patients with inflammatory bowel disease were from the retrospective group, and three were from the prospective group. The prevalence of inflammatory bowel diseases has been determined to be 0.0641% in the Düsseldorf area. RESULTS On the basis of these data, a 44-fold overrepresentation of inflammatory bowel diseases among the 213 patients with endocarditis was calculated with a statistical significance of p much less than 0.001. CONCLUSIONS Inflammatory bowel disease may be considered an independent risk factor for bacterial endocarditis. Reasons may be more frequent bacteremias as a result of the higher incidence of diagnostic and therapeutic interventions, as well as increased permeability of the damaged mucosa for bacteria and the therapeutic immunosuppression in patients with active inflammatory bowel disease. Prophylaxis for bacterial endocarditis should be carefully considered before expected bacteremias in patients with highly active inflammatory bowel disease even in the absence of cardiac factors predisposing to bacterial endocarditis.

Techniques and complications of transaortic subvalvular myectomy in patients with hypertrophic obstructive cardiomyopathy (HOCM)

The natural history of hypertrophic obstructive cardiomyopathy (HOCM) is usually characterized by development of mitral insufficiency, congestive heart failure (CHF) and sudden death. In patients (pts) belonging to at least clinical class III (NYHA) after failed medical therapy (beta-blocking agents and calcium-antagonists) surgery should be considered (by means of transaortic subvalvular myectomy). The history and development of different surgical techniques and procedures has been described in detail since 1958, when Cleland performed the first transaortic subvalvular myotomy. Our surgical series (1963-May 31, 1986) consists of 212 pts (mean age 40 years, range 6-73 years) with typical and atypical HOCM. The total hospital mortality rate was 6.6% (n = 14), which was reduced to 3.8% (n = 6), if only transaortic subvalvular myectomy (TSM) was performed (n = 160). In the group of 52 pts with additional surgical procedures the mortality rate was 15.4% (n = 8). The main problems occurred in pts with additional mitral valve replacement (MVR) (n = 15, three deaths). The rate of HOCM-related complications (secondary VSD, total AV-block, cerebral embolism, intraoperative re-myectomy) and those related to surgery (bleeding, pulmonary embolism, wound dehiscence, septicemia) was low. Therefore TSM for HOCM is a low-risk surgical procedure with a good long-term prognosis. However, in pts with a need for additional surgical procedures, the risk is considerably increased. Subjective impression of the pts and hemodynamic data indicate a clear clinical improvement postoperatively. Concerning long-term survival and reduction of the sudden death rate, our data do not allow a final judgement at the moment.

Hemodynamic long-term results after medical and surgical therapy of hypertrophic cardiomyopathies

The therapeutic effectiveness of propranolol, verapamil and surgery (transaortal subvalvular myectomy) in hypertrophic cardiomyopathy was assessed in 100 patients with hypertrophic obstructive cardiomyopathy (HOCM) and 12 patients with hypertrophic non-obstructive cardiomyopathy (HNCM) by means of exercise tests with hemodynamic measurements. The effects of propranolol were assessed in 13 HOCM patients, of verapamil in 68 HOCM patients and 12 HNCM patients, and of surgery in 31 HOCM patients after a mean of 3 to 9 months. Of the 68 verapamil-treated patients, 23 were reexamined once more after a mean of 38 months. Ten of the 31 surgically treated patients were reexamined after a mean of 52 months. In the studies performed within the first year of medical treatment or after surgery, verapamil was clinically and hemodynamically superior to propranolol, but not as effective as surgical treatment. Functional limitation according to the NYHA classification improved after propranolol in 31% of the patients, after verapamil in 41%, and after surgery in 94% of the cases. Improvements by more than one NYHA class were observed exclusively after surgical treatment. Maximal exercise capacity was, on average, not changed after propranolol, but increased after verapamil and, more substantially, after surgery. These different responses to treatment could be attributed to hemodynamic changes, especially concerning heart rate, stroke volume, cardiac output, arterio-venous oxygen difference and pulmonary artery pressure. In the case of verapamil, the beneficial hemodynamic effects occurred independently of the site of intraventricular obstruction in HOCM (subvalvular or midventricular), but seemed to be superior in HOCM as compared to HNCM. The late reexaminations, an average of 38 months after beginning verapamil treatment and 52 months after surgery, demonstrated that the initial salutary clinical and hemodynamic effects of verapamil were not maintained during long-term follow-up in the majority of patients, whereas they persisted or even intensified during long-term observation after surgery.

Frühe postoperative Veränderungen der systolischen und diastolischen Funktion in Ruhe und unter Belastung bei Patienten mit hypertroph-obstruktiver Kardiomyopathie (HOCM) nach Myektomie

Einleitung: Diese Studie hatte die simultane Erfassung von systolischer und diastolischer Funktion bei Patienten mit hypertroph-obstruktiver Kardiomyopathie und medikamentös therapierefraktären Beschwerden vor und nach Myektomie (M) zum Ziel. Methode: Hierzu wurden 19 Patienten (Alter 45 ± 16 Jahre, NYHA: 2,8 ± 0,3) 3,5 ± 3,6 Monate vor und 7,2 ± 4,5 Monate nach M mittels Echokardiographie, Swan-Ganz-Thermodilutionskatheter und simultaner Radionuklidventrikulographie untersucht. Resultate: Die Operation führte zu einer Reduktion von Ruhe- (40,1 ± 43,3 versus 7,6 ± 12,0 mm Hg, p ≤ 0,005) und Provokationsgradienten (92,4 ± 67,1 versus 21,3 ± 26,5 mm Hg, p ≤ 0,001). Die Beschwerdesymptomatik nach NYHA verbesserte sich auf 1,7 ± 1,4 (p ≤ 0,001). Die echokardiographisch bestimmte basale Septumdicke nahm ab (24,9 ± 6,3 versus 20,1 ± 6,8 mm; p ≤ 0,5), der enddiastolische Durchmesser stieg an (40,4 ± 5,2 versus 44,8 ± 7,1; p ≤ 0,05). Ebenso nahm die ergometrische Belastbarkeit von maximal erreichten 64,5 ± 19,2 auf 89,5 ± 24,0 Watt zu (p ≤ 0,001). Postoperativ fanden sich bei den systolischen Parametern eine verlängerte isovolumetrische Kontraktionszeit (65 ± 39 versus 112 ± 50 ms, p ≤ 0,01), eine verlängerte Zeit bis zur maximalen Ejektionsgeschwindigkeit (109 ± 40 versus 188 ± 42 ms, p ≤ 0,001) und in Ruhe eine verminderte linksventrikuläre globale Ejektionsfraktion (72 ± 12 versus 64 ± 11 % p ≤ 0,01). In Ruhe zeigte sich in den septalen und basalen Ventrikelanteilen und unter Belastung nur in den septalen Bereichen eine signifikante Minderung der Kontraktionen (p ≤ 0,05). Die Steigerungsfähigkeit der globalen und regionalen Ejektionsfraktionen unter Belastung war postoperativ nicht vermindert. Postoperativ zeigte sich unter Belastung ein signifikant größerer enddiastolischer Volumenindex (63 ± 19 versus 72 ± 17 ml * m−2, p ≤ 0,05). Der mittlere pulmonalkapilläre Verschlußdruck war sowohl in Ruhe (11,8 ± 3,8 versus 8,6 ± 2,4 mm Hg, p ≤ 0,05) als auch unter Belastung vermindert (27,0 ± 7,1 versus 20,4 ± 6,8 mm Hg, p ≤ 0,01). Schlußfolgerung: Patienten mit HOCM zeigen nach Myektomie eine deutliche Besserung der Belastungsfähigkeit. Die Operation geht mit einer Abnahme der basalen Septumdicke und einer Erweiterung des basalen enddiastolischen LV-Durchmessers einher. Konsekutiv-hämodynamisch ergibt sich eine modifizierte systolische Funktion mit einer septal-basal verminderten Ejektionsfraktion, eine Reduktion des intraventrikulären Gradienten begleitet von einer Besserung der diastolischen Funktion mit vermindertem Füllungsdruck bei vergrößertem enddiastolischem Volumen auf maximal erreichter Belastungsstufe. Introduction: In this study systolic and diastolic function in patients with hypertrophic obstructive cardiomyopathy (HOCM) and intractable complaints to medication were investigated before and after a mean of 7 months after myectomy. Methods: Investigations in 19 patients with HOCM included echocardiography, Swan-Ganz-thermodilution-catheter and radionuclide-angiography. Results: Myectomy resulted in a reduction of the intraventricular gradient at rest (40.1 ± 43.3 versus 7.6 ± 12.0 mm Hg, p ≤ 0.005) and under provocation (92.4 ± 67.1 versus 21.3 ± 26.5 mm Hg, p ≤ 0.001). Echocardiographically determined basal septal thickness was reduced (24.9 ± 6.3 versus 20.1 ± 6.8 mm; p ≤ 0.05) and diastolic diameter increased (40.4 ± 5.2 versus 44.8 ± 7.2; p ≤ 0.05). Exercise tolerance increased from the maximally achieved 64.5 ± 19.2 to 89.5 ± 24.0 W (p ≤ 0.001). Symptomatic status (NYHA) improved (1.7 ± 1.4 versus 2.8 ± 0.3 (p ≤ 0.001). Systolic parameters showed at rest an increase in isovolumetric contraction time (65 ± 39 versus 112 ± 50 ms, p ≤ 0.01), in time to peak ejection (109 ± 40 versus 188 ± 42 ms, p ≤ 0.001), and a reduced left ventricular ejection fraction (72 ± 12 versus 64 ± 11%, p ≤ 0.01). Analysis of regional ejection fraction revealed a significant reduction of ejection fraction in the basal septal region (p ≤ 0.05). Increase of global and regional ejection fraction under exercise was still preserved. Mean pulmonary capillary wedge pressure was significantly reduced at rest (11.8 ± 3.8 versus 8.6 ± 2.4 mm Hg, p ≤0.05) as well as under exercise (27.0 ± 7.1 versus 20.4 ± 6.8 mm Hg, p ≤ 0.01), whereas left ventricular enddiastolic volume index (63 ± 19 versus 72 ± 17 ml * m−2, p ≤ 0.05) was significantly increased. Conclusions: In patients with HOCM, myectomy reduces intraventricular gradient, increases exercise capacity, and is accompanied by improved diastolic function parameters, while systolic function parameters are generally reduced.

Variability and reproducibility of morphologic findings in endomyocardial biopsies of patients with hypertrophic obstructive cardiomyopathy

Morphometric investigations of endomyocardial catheter biopsies (EMCB) promise to give more insight in the morphologic-functional relationship in patients with hypertrophic obstructive cardiomyopathy (HOCM), and may disclose the morphologic course of the disease. Variability and reproducibility of morphologic findings in EMCB of patients with HOCM are still undefined. We investigated 112 right ventricular biopsies of 25 patients with HOCM of a mean age of 38.3 +/- 15.2 years (six women, 19 men). Mean EMCB size was 0.755 +/- 0.567 mm2. 28.6% of EMCB were not suitable for morphometric investigation. Variability of morphologic findings was investigated by analysis of variance and described by the coefficient of variation (CV). Sampling variabilities of muscle fiber diameter (CV = 5%), volume density of interstitium (CV = 9%) and fibrous tissue (CV = 17%) differed. Reproducibility in terms of intra- and interobserver variations for these variables reached a comparable level, diminishing observed differences between biopsies from the same heart, which became non-significant. Sampling variability of endocardial thickness (CV = 79%) and muscle fiber disarray (CV = 100%) were higher than intra- and interobserver variations. For an estimate of muscle fiber size, one EMCB specimen is sufficient, three for volume density of interstitium and nine for fibrous tissue. High sampling variability of endocardial thickness and muscle fiber disarray demand numerous biopsies; here the greatest measured value from a few biopsies may be of more clinical relevance. From our data, five EMBC are desirable, and give the most information at an acceptable strain.

Evidence for muscle fiber hyperplasia in the septum of patients with hypertrophic obstructive cardiomyopathy (HOCM). Quantitative examination of endomyocardial biopsies (EMCB) and myectomy specimens

Asymmetric thickening of the septum is one of the hallmarks of hypertrophic obstructive cardiomyopathy (HOCM). Endomyocardial biopsies (EMCB) from the right side of the septum and myectomy specimens from its left part were morphometrically investigated to determine the size of septal myocytes, as well as the volume density of the interstitium and fibrous tissue, and to estimate the number of transseptal muscle fiber layers. EMCBs of seven patients with normally shaped hearts, taken as controls (N), EMCBs of seven consecutively examined patients with HOCM (HOCM 1), and of seven HOCM patients with additionally available myectomy specimens (HOCM 2) were evaluated. In myectomy specimens muscle fiber thickness and volume density of the interstitium and fibrous tissue were significantly increased, as compared with the findings in the EMCBs. The echocardiographically determined septal thickness was increased by 93% in HOCM 1 and by 150% in HOCM 2 compared with controls; however, the increase in muscle fiber thickness and volume density of the interstitium did not give a sufficient explanation for the increased septal thickness in both groups of HOCM. Based on EMCB data, the estimated number of septal muscle fiber layers was 715 +/- 93 in group N, 1242 +/- 149 in HOCM 1, and 1119 +/- 177 in HOCM 2, while 810 +/- 232 layers were estimated according to the findings from myectomy specimens. Taking into account that EMBC represent only 1 mm of septal thickness, and myectomy specimens up to 15 mm, an increase in the septal muscle cell layers of about 30% can be estimated in HOCM hearts.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical Technique in Subvalvular and Midventricular Hypertrophic Obstructive Cardiomyopathy (HOCM)

Cleland, in 1958 performed the first subvalvular myotomy for relief of hyper-trophie obstructive cardiomyopathy (HOCM); following him came a variety of surgical procedures. In our clinic we principally use the Morrow technique (subvalvular myectomy) which was modified for better initial pressure gradient reduction, improvement of diastolic relaxation, and decrease of concomitant mitral insufficiency. Since 1963 a total of 253 patients were operated upon for symptomatic HOCM (NYHA class III or IV) after failing medical therapy (β-blockers, calcium antagonists). Their mean age was 41–45 years (range, 6–74 years). The male/female radio was 1.7 : 1. In 230 patients a typical subvalvular significant obstruction was present, while 23 patients had an additional, atypical midventricular obstruction. The surgical steps for both variations of HOCM are described in detail. The hospital mortality for transaortic subvalvular myectomy was 3.2% (6 of 190 patients), while for patients needing additional cardiac procedures it was 12.7% (8 of 63 patients). Taking account of the natural history of HOCM involving continuing deterioration, all patients were followed postoperatively (100%). The yearly death rate (HOCM-related) was 1.2%. However, the majority of the surviving patients (more than 6 months) demonstrated considerable long-term clinical improvement regarding complaints, physical capacity, and hemodynamics. Thus, operative relief of symptomatic HOCM is of long-term benefit for the patients.

Effects of therapeutic interventions on minimal cardiac transit times and volume parameters in hypertrophic cardiomyopathy

45 patients with hypertrophic obstructive cardiomyopathy (HOCM) and 18 patients with hypertrophic non-obstructive cardiomyopathy (HNCM) underwent simultaneous measurements of pulmonary artery pressure and minimal transit times (MTTs) of an intravenously injected bolus of indium-113m-EDTA through the heart at rest and during exercise in supine position. At rest, rate-corrected left and right ventricular MTTs were in the lower normal range, whereas left atrial and, to a lesser degree, right atrial MTTs were abnormally prolonged, indicative of high ventricular ejection fractions and impaired atrial ejection. During exercise, ventricular MTTs rose slightly but remained within the normal range, which corresponds to a slight fall in ventricular ejection fractions. Atrial MTTs exhibited, in contrast, a substantial further prolongation. Together with an abnormal increase in pulmonary artery pressure in the majority of patients, these findings suggest an aggravation of inflow impairment to both ventricles during exercise. There was no quantitative difference between HOCM and HNCM patients suggesting that impaired atrial ejection due to impaired diastolic function is of major pathophysiological importance irrespective of a possible additional role of left ventricular outflow obstruction in HOCM. The influence of surgical therapy (transaortal septal myectomy) was studied in 12 patients with HOCM. A significant increase in left ventricular MTTs to the upper normal range, indicative of a depression of left ventricular ejection fractions to the lower normal range, and a significant shortening of left atrial and pulmonary MTTs were observed, whereas corresponding changes in the right heart were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)