Comparison of dual-chamber pacing with nonsurgical septal reduction effect in patients with hypertrophic obstructive cardiomyopathy.

OBJECTIVES: The aim of the study was to compare the influence of dual-chamber pacing vs. nonsurgical septal reduction on hemodynamic and morphological parameters in patients with obstructive form of hypertrophic cardiomyopathy. METHODS: Nineteen patients with dual-chamber pacing (group I) and 9 patients who underwent nonsurgical septal reduction (group II) were studied at baseline and after a 6-month follow-up. The changes of left ventricular outflow tract gradient and posterior wall thickness (as an index of left ventricular hypertrophy regression) were compared. RESULTS: The baseline left ventricular outflow tract gradient was comparable between group I and group II (77+/-25 vs. 82+/-25 mm Hg, p>0.05). At 6-month follow-up, the left ventricular outflow tract gradient was reduced to a similar level in both groups (28+/-19 vs. 25+/-12 mm Hg, p>0.05). At baseline, posterior wall hypertrophy was comparable between groups (12.9+/-1.7 vs. 13.6+/-2.2 mm, p>0.05). During follow-up, the posterior wall thickness was unchanged in the pacing group (12.9+/-1.7 vs. 12.6+/-1.6 mm, p>0.05), whereas nonsurgical septal reduction induced regression of left ventricular hypertrophy in myocardial region remote from the infarcted septal segment (13.6+/-2.2 vs. 10.5+/-2.3 mm, p<0.003). CONCLUSION: Despite comparable reduction of instantaneous left ventricular outflow tract gradient, the nonsurgical septal reduction decreased posterior wall thickness, whereas pacing did not reduce left ventricular hypertrophy. Thus, regression of left ventricular hypertrophy that appeared solely after nonsurgical septal reduction may reflect the more permanent reduction of left ventricular pressure overload. Thus, not only hemodynamic but also morphological benefit from nonsurgical septal reduction seems to indicate the superiority of this method over dual-chamber pacing.

The importance of ventricular septal morphology in the effectiveness of dual chamber pacing in hypertrophic obstructive cardiomyopathy.

It has been reported that older patients with hypertrophic obstructive cardiomyopathy (HOCM) benefited the most from dual chamber (DDD) pacing. Since in older patients the distribution of septal hypertrophy and left ventricular (LV) cavity shape differs from that in younger patients, we decided to study the efficacy of DDD pacing on the reduction of LV outflow tract (LVOT) gradient in different patterns of septal hypertrophy. We compared HOCM patients with nonreversed septal curvature, thus preserving the elliptical LV cavity contour (common in the elderly), (group I) versus patients with reversed septal curvature, deforming the LV cavity to a crescent shape (common in the young), (group II). Eighteen HOCM patients were studied (11 patients in group I and 7 patients in group II). After implantation of a DDD pacemaker, the LVOT gradient was measured using Doppler echocardiography at various programmed AV delay intervals to determine the maximal percentage decrease of LVOT gradient from baseline. The measurement was repeated after at least a 6-month follow-up (chronic DDD pacing). The baseline LVOT gradient was comparable between groups (79 +/- 28 vs 81 +/- 25 mmHg, P = 0.92). The LVOT gradient reduction at acute DDD pacing was significantly greater in group I than group II (61 +/- 18% vs 23 +/- 10%, P = 0.0001). This difference in favor of the patients from group I was maintained at midterm follow-up (69 +/- 17% vs 40 +/- 17% P = 0.0076). In conclusion, patients with normal septal curvature and preserved elliptical LV cavity shape had a greater reduction of LVOT gradient after DDD pacing than patients with reversed septal curvature deforming LV cavity. The proposed criterion assessing the septal curvature may be useful to predict the efficacy of DDD pacing in the reduction of LVOT gradient.

Balloon positioning difficulties during nonsurgical septal reduction therapy in a patient with hypertrophic obstructive cardiomyopathy.

Dual chamber (DDD) pacing and catheter-based nonsurgical septal reduction therapy (NSRT) with ethanol are evaluated for treatment of patients with hypertrophic cardiomyopathy. This report describes a patient with hypertrophic cardiomyopathy and left ventricular outflow tract obstruction who had failed to respond to DDD pacing but showed benefit from subsequent NSRT. Procedural difficulties during NSRT due to massive septal hypertrophy are presented.

[The effect of myocardial revascularization on global and regional systolic and diastolic left and right ventricular function]. / Wplyw zabiegów rewaskularyzacyjnych na skurczowa i rozkurczowa czynnosc lewej i prawej komory serca.

UNLABELLED: The objective of the study was to evaluate the effect of myocardial revascularization (PTCA, CABG) on right and left ventricular systolic and diastolic function, and segmental wall motion in patients with coronary artery disease. The study population consisted of 27 patients, ranging in age from 36 to 67 years (mean age 51.1 +/- 8.8). CABG and PTCA were performed in 17 and 10 patients, respectively. All patients underwent radionuclide angiocardiography at baseline and 3 months after the procedure. The following parameters were measured: ejection fraction (EF), 1/3EF, maximal emptying rate (MER), maximal filling rate (MFR), 1/3 filling fraction (1/3FF), and segmental wall motion in segments S1 to S9. Increased left ventricular EF was observed in 29.4% of patients after CABG and in 40% of patients after PTCA. Segmental wall motion in the revascularized area also improved except for septal segments in the left ventricle in patients after CABG. Global right ventricular function remained practically unchanged both after CABG and PTCA. However, EF of right ventricular septal segments increased after CABG: S1--24.58 +/- 11.7% vs 33.4 +/- 14.7%, S9--35.52 +/- 13.7% vs 46.8 +/- 15.9%. CONCLUSION: Myocardial revascularization improves left ventricular systolic and diastolic function with no effect on global right ventricular performance. After CABG the ejection fraction of septal segments was altered. Successful PTCA of LAD improves EF of septal segments in the left ventricle.

Influence of an early adrenergic blockade on thrombotic infarct size and myocardial metabolism.

To evaluate the extent to which the protective effect of metoprolol was accompanied by changes in myocardial oxygen consumption and metabolism, thrombotic occlusion of coronary artery followed by infusion of metoprolol or placebo was performed in twenty four German Shepherds. To restore a coronary blood flow rt-PA was administered. Plasma levels of oxygen, glucose, lactic acid, non esterified fatty acids, triacylglyceride and adenosine breakdown products were measured before and at the end of the occlusion and in the early and late reperfusion periods. Regional myocardial blood flow was measured by means of radioactive tracer microspheres. Infarct size was estimated after perfusion and staining of excised hearts with Evans blue. Plasma levels of metoprolol were determinated before the end of occlusion and during reperfusion and therapeutic concentrations were confirmed. The infarct size was smaller in dogs receiving metoprolol (21.6 +/- 20.7 vs 43.0 +/- 17.3% p. < 0.02). Coronary collateral blood flow was greater in metoprolol than in placebo dogs (18.68 +/- 7.58 vs 11.05 +/- 6.10 ml/min/100g, p. < 0.01). As a consequence of myocardial ischemia a shift toward carbohydrate utilization, the myocardial lactate release and the accompanying symptoms of diminished myocardial lipid uptake were observed. A washout of adenosine degradation products during early reperfusion was also noticed. In beta 1 blocked animals the reduction of myocardial oxygen consumption and preserved myocardial uptake of lactate and non esterified fatty acids were documented.

Effect of exercise rehabilitation on heart rate variability in hypertensives after myocardial infarction.

OBJECTIVE: The aim of the study was to find out whether the presence of hypertension affects heart rate variability in patients rehabilitated after myocardial infarction. DESIGN: Echocardiography, exercise testing and 24 h Holter monitoring were performed before and after 27 days of early postdischarge cardiac rehabilitation. PATIENTS: The study population consisted of 64 patients aged 34-65 years (mean+/-SD 51.6+/-6.6) discharged from hospital after a first myocardial infarction who were subdivided into two groups, group A comprising 34 patients with arterial hypertension which had lasted 4.8+/-2.1 years and group B comprising 30 normotensives. MAIN OUTCOME: We expected exercise rehabilitation to affect heart rate variability, exercise tolerance and myocardial ischemia in patients after myocardial infarction with and without arterial hypertension. RESULTS: At baseline no intergroup differences were seen in the duration of exercise, workload and heart rate variability parameters. All parameters increased significantly after cardiac rehabilitation (P < 0.01): SD of all normal RR intervals 123.4+/-30.0 versus 123.8+/-30.0 ms; SD of the averages of normal RR intervals in all 5-min segments of the entire recording 115.1+/-30.5 versus 116.3+/-28.3 ms; mean of the SD of all normal RR intervals for all 5-min segments of the entire recording 49.0+/-12.5 versus 48.3+/-11.8 ms; square root of the mean of the sum of the squares of differences between adjacent RR intervals 29.7+/-9.1 versus 28.0+/-8.5 ms; percentage of differences between adjacent RR intervals > 50 ms 7.9+/-6.0 versus 7.1+/-6.1% (group A versus group B, respectively, NS). The duration of exercise and the workload were significantly increased (the rise was higher in normotensives). No differences were seen in the frequency and severity of silent myocardial ischemia. CONCLUSIONS: Early stationary exercise rehabilitation after myocardial infarction improves heart rate variability parameters and exercise tolerance both in hypertensives and in normotensives.

[Dependence of a drop in blood pressure in pulmonary circulation and in the right heart on dosage of isosorbide dinitrate]. / Zaleznosc spadku cisnienia w krazeniu plucnym i w prawym sercu od dawki dwunitroizosorbitu.

An effect of isosorbide dinitrate on blood pressure values in the pulmonary circulation and the right heart has been investigated in 25 patients with a history of the first transmural myocardial infarction. Group I including 12 patients has been given 5 mg isosorbide nitrate in a 60-minute intravenous infusion while group II of 13 patients has been given 10 mg of the drug in the same way. Both groups have been matched in clinical data and blood pressure value in the pulmonary circulation which has been normal. Pulmonary blood pressure has been measured with Swan-Ganz catheter prior to the administration of drug, and 15, 30, 45 and 60 minutes following an infusion. Isosorbide dinitrate in a dose of 5 mg did not decrease blood pressure in the pulmonary circulation statistically significantly. The differences in blood pressure falls did exceed 9%. Filling pressure in the right ventricle did not change either while systolic blood pressure decrease by 16.6%. A double dose of isosorbide dinitrate reduced blood pressure in the pulmonary artery by about 1/3 of the baseline value, and blood pressure in the right ventricle (mean right atrial pressure) by 57.2%. Both systolic and diastolic arterial pressures were reduced. Isosorbide dinitrate reduced blood pressure in the pulmonary circulation in patients who underwent myocardial infarction, and hypotensive effect has been dose-related. A reduction in the right ventricular filling pressure has been a one of important mechanisms decreasing pulmonary pressures.

[Constrictive pericarditis]. / Zaciskajace zapalenie osierdzia.

Etiology of constrictive pericarditis is diversified. In recent years the role of viral and iatrogenic factors (X-ray therapy, cardiac surgery) has increased. Clinical manifestations, including subjective complaints, resemble those in congestive heart failure although the mechanism of hemodynamic disorders is different--namely impairment of ventricular filling and diastolic performance. One encounters major difficulties while differentiating constrictive pericarditis from restrictive cardiomyopathy. In some patients conservative treatment is effective, in a majority of them surgical operation, pericardiectomy is the treatment of choice.

[Arrhythmia and silent myocardial ischemia in patients after myocardial infarction]. / Zaburzenia rytmu i ciche niedokrwienie miesnia sercowego u chorych po zawale serca.

In a group of 37 patients (30 men and 7 women aged from 36 to 67 years, men age 50.3) after a first acute myocardial infarction the frequency was analysed of the episodes of silent myocardial ischaemia with ST depression, and its correlation with arrhythmia was studied during outpatient ECG monitoring and exercise test on cycle ergometer. Outpatient ECG monitoring during 24 hours was done with a recorder Oxford Medilog MR-14 AM System 8-12 weeks after the onset of infarction. In the same patients the exercise test on cycle ergometer (KF-12 Medicor) was done by graded exercise method with workload increasing by 25 Watt every 3 minutes. The test was terminated after achieving 85% maximal heart rate or appearance of limiting signs. Each episode of ST depression by 1.0 mm or more lasting over 1 minute with horizontal or sloping ST depression 80 msec from point J was regarded in both cases as ischaemic. During outpatient ECG monitoring it was observed that 30 out of 37 (81.1%) had 138 episodes of ST depression, including 45 (32.6%) associated with pain and 93 (67.9%) painless (p less than 0.02). The mean maximal ST depression during painful and painless episodes was respectively 3.4 +/- 1.3 mm and 2.9 +/- 1.1 mm (p less than 0.03). Out of 30 patients 7 (23.3%) had 54 episodes of various arrhythmias, with bursts of ventricular ectopic beats, in one patient supraventricular tachycardia and in another one grade II atrioventricular block developed. These patients had also isolated ventricular ectopic beats. In 6 patients (20.0%) arrhythmia was temporarily associated with signs of ischaemia with ST depression.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of isosorbide dinitrate on left and right ventricular systolic time intervals in patients after myocardial infarction]. / Wplyw dwunitroisosorbitu na podokresy skurczu lewej i prawej komory serca chorych po przebytym zawale serca.

The purpose of the study was to assess effects various doses of isosorbide dinitrate (ISDN) on left and right ventricular systolic time intervals in patients after myocardial infarction. The study population consisted of 25 patients who were eight weeks after their first transmural myocardial infarction. Twelve patients were given 5 mg of ISDN by an intravenous infusion for 60 min, and remaining 13 patients were given 10 mg of ISDN in a similar manner. Subgroups did not differ with respect to their initial arterial blood pressure (mean = 133.3) 82.9 vs 134.3 (87.1 mm Hg) and systolic pulmonary arterial pressure (mean = 27.2 vs 28.8 mm Hg). The infarct localization was also similar. Left ventricular systolic time intervals were calculated noninvasively, whereas right ventricular systolic time intervals were measured from simultaneous electrocardiographic, phonocardiographic and pulmonary arterial pressure tracings. Both left and right ventricular systolic time intervals were determined before and at 15 and 60 min after the drug administration. Student's t-test for unpaired and paired variables was used to test for statistical significance. Changes in the parameters studied at 60 min of the ISDN infusion were greater than at 15 min, and therefore only they are taken into account in the presentation of the results. During a 5 mg infusion of ISDN arterial blood pressure showed a tendency to decrease. Left ventricular ejection time shortened (-3.9%) and the pre-ejection period lengthened (+ 21.9%). The pulmonary artery pressure showed minimal tendency to decrease. The right ventricular systolic time intervals showed a similar tendency but the changes were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

[The role of nitroglycerin in limiting the area of necrosis in myocardial infarction]. / Rola nitrogliceryny w ograniczeniu strefy martwicy zawalu miesnia serca.

Clinical course of myocardial infarction and prognosis depend mainly on the extent of necrosis. A large number of cells in the neurotic zone, despite metabolic changes and contractility disorders may be salvaged providing that the treatment is initiated early enough. Intravenous nitroglycerin is one of the available agents used in limiting infarct size. Its beneficial effects on the myocardial cells in the border zone of the infarct result from a reduction in ventricular preload and afterload, an improvement of myocardial compliance and ventricular contractile function as well as from a redistribution of myocardial blood flow. The direct action of nitroglycerin on the coronary arteries and collaterals without "steal effecta" is also of importance. The results of clinical experiments with intravenous nitroglycerin in acute myocardial infarction are encouraging. By using various techniques to estimate the amount of salvage in the myocardium at risk various authors report a 30-41% salvage with nitroglycerin therapy.

[Isosorbide dinitrate treatment of silent myocardial ischemia in patients after myocardial infarction]. / Próba leczenia dwunitroisosorbitem cichego niedokrwienia miesnia serca u chorych po zawale serca.

In a group of 17 men and women aged 38-65 years (means = 51.1) three months after the first myocardial infarction we studied changes in silent ischemic ST segment depression by using Holter monitoring and exercise stress testing before and after 120 mg/daily of oral isosorbide dinitrate (Isoket). Repeated ECG monitoring and exercise stress test were performed after two weeks. It was found that before isosorbide dinitrate therapy 16 out of 17 patients had 56 episodes of ST segment depression of 1-5 mm including 6 (37.5%) symptomatic episodes and 10 (62.5%) asymptomatic episodes. The number of asymptomatic episodes after isosorbide dinitrate therapy decreased more than five times (p less than 0.001), their duration was three times shorter (p less than 0.01). ST segment depressions were also significantly smaller. During isosorbide dinitrate therapy the duration of stress test was almost doubled and the achievable heart rate increased (p less than 0.02; p less than 0.05). The magnitude of ST segment depression during exercise testing also decreased significantly (p less than 0.01) and at heart rate below 100 beats/min ischemic ST segment depression were not observed, in contrast to pre-treatment period. Thus it may be concluded that silent myocardial ischemia is a frequent event in patients after the first myocardial infarction and isosorbide dinitrate significantly decreases the number of symptomatic and asymptomatic episodes detected by Holter monitoring.

[Silent myocardial ischemia in patients after myocardial infarction]. / Ciche niedokrwienie miesnia sercowego u chorych po przebytym zawale serca.

Twenty-six men and women, aged 36-65 years, were studied 8-12 weeks after the first myocardial infarction with regard to silent ischemic ST-segment depression and heart rate by using 24-hour ambulatory electrocardiography and bicycle exercise testing. In 22 patients ambulatory ST-segment recordings revealed 81 episodes of ST-segment depression, including 34 (41.9%) painful and 47 (58.1%) painless episodes. Mean maximal ST-segment depression during symptomatic and asymptomatic episodes was 3.6 +/- 1.0 mm and 2.4 +/- 1.1 mm, respectively (p less than 0.02). Painless episodes most frequently occurred between 06.00 a.m. and 12.00 a.m. Ambulatory monitoring revealed a twofold increase in painful episodes at heart rate below 100 beats/min, whereas at heart rate above 125/min painless episodes were more frequent. Exercise testing showed a sevenfold increased incidence of ST-segment depression also at heart rate above 125 beats/min. In conclusion, silent myocardial ischemia is a frequent event in patients shortly after the first myocardial infarction, and painless episodes occur particularly frequently at high heart rates. Episodes of silent ischemia are found more frequently during ambulatory ECG monitoring than exercise testing. Studies on silent myocardial ischemia may be particularly relevant in the detection of the risk of myocardial infarction.