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PubMed2000

Cardiac function, physical exercise capacity, and quality of life during long-term thyrotropin-suppressive therapy with levothyroxine: effect of individual dose tailoring.

As recently claimed, TSH-suppressive therapy with L-T4 may have adverse effects on the heart, but these results have not been consistently confirmed. We assessed cardiac function by clinical, echocardiographic, and ergometabolic criteria in 19 patients (16 women and 3 men) receiving long term L-T4 at a fixed daily dose ranging from 1.8-4.0 microg/kg. The results showed significant alterations in several cardiac parameters suggestive of subclinical hyperthyroidism. In particular, intraventricular septum thickness (10.0+/-1.4 vs. 8.1+/-1.1 mm), left ventricular posterior wall thickness (9.4 1.5 vs. 8.1+/-1.1 mm), end-diastolic dimension (47+/-4 vs. 44+/-3 mm), and left ventricular mass index (102+/-15 vs. 75+/-15 g/m2) were significantly increased compared to values in age- and sex-matched euthyroid controls. Exercise tolerance (expressed as maximal tolerated workload; 102+/-14 vs. 117+/-12 watts), maximal VO2 achieved at peak exercise (maximum VO2, 17.3+/-3.3 vs. 21.9+/-2.5 mL/min x kg), and anaerobic threshold (expressed as a percentage of VO2max, 46.5+/-8.4 vs. 56.2+/-6.6) were significantly reduced in L-T4-treated patients. The L-T4 dose was then reduced to the minimal amount able to keep the serum TSH concentration at 0.1 mU/L or less in 7 patients who were reevaluated 6 months after the initial study. This individual tailoring of the TSH-suppressive L-T4 dose was in all cases associated with normalization of all echocardiographic and ergometabolic parameters. In conclusion, our findings show that abnormalities of heart morphology associated with impaired exercise performance occur as a consequence of long term therapy with fixed TSH-suppressive doses of L-T4, but that these abnormalities improve or disappear after careful tailoring of TSH-suppressive therapy.

Adult↗
PubMed2000

Changes in cardiac function at rest before and after treatment in primary hypothyroidism.

The aim of the present study was to investigate in hypothyroid patients the reversibility of the prolongation of electromechanical delay and of the impairment of early diastolic relaxation as measured by radionuclide ventriculography after restoration of euthyroidism. We also evaluated Doppler echocardiography in relation to scintigraphic findings. Twenty-six consecutive hypothyroid patients were studied at diagnosis and after treatment. The time to peak ejection decreased (161 +/- 6 vs 145 +/- 5 ms; p = 0.03) without changes in global systolic function (ejection fraction). The peak filling rate was reversible as well: 2.6 +/- 0.1 versus 3.0 +/- 0.2 end-diastolic volume/s; p = 0.003. No significant changes in systolic and diastolic cardiac function or ventricular geometry were detected by Doppler echocardiography. However, subanalysis of profoundly hypothyroid patients (free T4 < 4.5 pmol/L, n = 8) revealed a decrease in the septal wall thickness (9.9 +/- 0.7 vs 8.3 +/- 0.4 mm, p = 0.01) and increases in early peak transmitral inflow velocity (53 +/- 4 vs 65 +/- 4 cm/s, p = 0.03), as well as left ventricular end-diastolic diameter (4.8 +/- 0.1 vs 5.1 +/- 0.2 cm, p < 0.05) after treatment. Thus, in primary hypothyroidism, a subtle reversible prolongation of contraction without major changes in global systolic function and a decrease in early active relaxation is observed by radionuclide ventriculography. Echocardiography shows changes only in severely hypothyroid patients.

Adolescent↗
PubMed2002

Pretreatment of donors with endothelin receptor antagonist TAK-044 improves cardiac functional recovery following preservation with University of Wisconsin solution.

OBJECTIVE: Previous studies suggest that endothelin-1 (ET-1) plays a role in myocardial ischemia/reperfusion injury. Although administration of an endothelin receptor antagonist to the recipient has been shown to improve myocardial function after ischemia/reperfusion in a rat heart transplantation model, the effect of administering an endothelin receptor antagonist to the donor has not yet been examined. This study was designed to investigate the effects of pretreating donors with an ET(A)/ET(B) endothelin receptor antagonist (TAK-044) on myocardial function after cold preservation of a rat heart. DESIGN: Male rats were pretreated with normal saline (control group, n = 8), TAK-044 (TAK group, n = 8, 1 mg/kg). Following cardiac arrest using cardioplegia, we washed out the coronary vascular beds with cold University of Wisconsin solution followed by 6-h preservation. After preservation, the hearts were mounted on a Langendorff apparatus to estimate aortic flow (AF), coronary flow (CF), cardiac output (CO), systolic pressure (SP), heart rate (HR), and rate-pressure product (RPP: HR x SP). The concentration of lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) within the coronary perfusate during reperfusion was measured. RESULTS: AF, SP, and CO were significantly greater in the TAK group than in the control group (p = 0.0045, 0.004, and 0.0295, respectively). CONCLUSION: Pretreatment of donors with a nonselective endothelin receptor antagonist (TAK-044) improved cardiac functional recovery following preservation and may be beneficial for prolonged myocardial preservation.

Adenosine↗
PubMedDate not supplied

Systolic and diastolic cardiac function in acromegaly. An echocardiographic study.

The aim of this study was to establish the existence of primary acromegalic cardiomyopathy different from the cardiovascular complications often associated with acromegaly. Thirty-four acromegalic patients, referred to our non-invasive laboratory and divided into two groups on the basis of the presence of hypertension, underwent echocardiographic studies. A control group of 34 subjects individually matched with the patients for age, sex, and blood pressure values was also studied. To evaluate cardiac function during exercise, the normotensive acromegalics, the control group, and a group of 9 athletes with left ventricular mass comparable to that of the acromegalic subjects underwent a handgrip test. Cardiac mass was increased in all patients; hypertensive patients had a greater increase than normotensive patients (144.9 +/- 38 vs 120.9 +/- 20.8 g/m, p < 0.02). Systolic wall stress and percent fractional shortening, although similar to the values confirmed in controls, were modified in the hypertensive patients (wall stress 77.5 +/- 9.3 vs 60.8 +/- 9.4 dyne/cm2, p < 0.01). In all patients, diastolic function at rest was similar to that in controls, although the hypertensive patients had deteriorated diastolic function (E peak 56.9 +/- 12.4 vs 71 +/- 15 cm/s, p < 0.01; A peak 70.4 +/- 21.1 vs 52.3 +/- 16.4 cm/s, p < 0.03; E/A ratio 0.89 +/- 0.37 vs 1.38 +/- 0.35, p < 0.02). During handgrip testing, wall stress in both the normotensive acromegalics and the control subjects increased but remained unchanged in the athlete group; percent fractional shortening decreased in all patients and controls but increased slightly in the athlete group. In conclusion, cardiac hypertrophy caused by GH hyperincretion does not improve acromegalic heart activity: diastolic function, although normal at rest, appears deficient during isometric exercise.

Acromegaly↗
PubMed1995

Fetal cardiac function and ductus arteriosus during indomethacin and sulindac therapy for threatened preterm labor: a randomized study.

OBJECTIVE: The purpose of this randomized study was to evaluate the effects of indomethacin (10 patients) and sulindac (10 patients) given for 4-days on the fetal cardiac function and ductus arteriosus in pregnancies complicated by threatened premature labor between 28 and 32 gestational weeks. STUDY DESIGN: By use of pulsed color Doppler techniques the pulsatility index in fetal ductus arteriosus was calculated. Peak systolic velocities in the fetal ascending aorta and pulmonary trunk were also measured. By M-mode echocardiography both ventricular inner end-diastolic and end-systolic diameters were measured and ventricular fractional shortenings were calculated. Tricuspid valve regurgitation was evaluated by pulsed and color Doppler techniques. The ultrasonic examinations were made before and 4, 24, 48, and 72 hours after the start and 24 hours after the end of medication. RESULTS: Indomethacin significantly decreased the mean pulsatility index in fetal ductus arteriosus 4 hours after the beginning of medication. This decrease became greater later during medication, and it was associated with a significant increase in both ventricular inner end-diastolic diameters and with a significant decrease in right ventricular fractional shortening. The mean pulsatility index in the fetal ductus arteriosus increased to control values at 24 hours after the end of medication. Sulindac significantly decreased the mean pulsatility index in fetal ductus arteriosus only 24 hours after the beginning of medication. All other mean pulsatility index values did not differ from control values. Other cardiac parameters remained unchanged during sulindac treatment. CONCLUSION: Indomethacin has a significant reversible constrictive effect on the fetal ductus arteriosus that is associated with secondary changes, especially in the right ventricle. Sulindac seems to have only a mild and transient constrictive effect on the fetal ductus arteriosus.

Ductus Arteriosus↗
PubMed1977

Cardiac function and exercise training in conscious dogs.

Exercise training (T) was accomplished in 21 mongrel dogs. The animals were instrumented to measure ascending aortic flow, left ventricular pressure, and left atrial pressure. They were allowed to recover for 4 wk following surgery before accomplishing a standardized submaximal test (SMT). The exercise program alternated daily between sprint and endurance training. During T, the animals were tested while lying quietly on a laboratory table as well as during the SMT. In six animals, ventricular function curves (VFC) were obtained by rapid volume loading at similar time intervals as the SMT. Heart rate increased during the SMT but was found to be reduced in the T animals by an average of 20 beats/min. The maximum derivative of left ventricular pressure (P) increased during the SMT in T animals by an average of 2,200 Torr/s above the untrained animals. The VFC was lower in T animals than untrained animals because of a reduction in heart rate response. Results indicate a reflex adaptation of the nervous system with training to improve cardiac function.

Animals↗
PubMed1992

Acute improvement of cardiac function with intravenous L-propionylcarnitine in humans.

As the myocardial carnitine content, a key control factor in myocardial oxidative metabolism and energy transfer, is reduced in heart failure, administration of L-propionylcarnitine (LPC), a potent analogue of L-carnitine, potentially may improve cardiac function, possibly through a positive inotropic effect. As its hemodynamic profile is unknown in humans, 32 fasting normotensive patients with coronary artery disease received either 15 mg/kg of LPC (n = 16) or vehicle (mannitol/acetate, n = 16) infused over 5 min. Hemodynamic, radionuclide [peak ejection and filling rates (PER and PFR, respectively)], and metabolic variables (myocardial O2, lactate, and carnitine uptake) were studied at baseline and 1, 3, 5, 10, 15, and 45 min postdrug. The baseline ejection fraction was depressed in LPC patients (40 +/- 3% vs. 48 +/- 4% in the vehicle group, p less than 0.05) as a result of a significant high incidence of previous infarctions. Immediately following LPC, the cardiac total carnitine uptake changed from 102 +/- 181 to 5,335 +/- 1,761 mumol/L (p less than 0.05). In both groups, left ventricular systolic and end-diastolic pressures increased significantly by 5 and 20%, respectively, during the first 5 min. In the vehicle group, contractility decreased by 5%, accompanied by a significant 11% fall in the stroke volume. In contrast, following LPC, isovolumetric contractility indices remained unaltered. Instead, both the PER and PFR improved by 16% at 45 min. Moreover, the cardiac output increased by 8%. LPC did not affect systemic or coronary hemodynamics. Lactate uptake increased by 42%, but myocardial O2 consumption did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1999

Beneficial effects of long-term treatment with enalapril on cardiac function and heart rate variability in patients with old myocardial infarction.

BACKGROUND: The beneficial effects of the early use of angiotensin-converting enzyme inhibitors (ACEis) in patients with acute myocardial infarction (MI) are well documented. However, the effects of ACEis in patients with an old MI and preserved cardiac function have not yet been studied. We examined the effects of 12 months of enalapril treatment in patients with previous MI. METHODS AND RESULTS: Thirteen patients with an old MI and no overt congestive heart failure (CHF), aged 70 +/- 2 years, were treated with enalapril for 12 months. We also included 13 age- and sex-matched control patients who had a similar clinical background but were not treated with enalapril. Holter electrocardiography and echocardiography were performed at entry and after 12 months of treatment. Heart rate variability, low- and high-frequency powers (LF and HF), and the ratio between LF and HF (LF/HF) were analyzed. Changes from baseline to 12 months in HF, LF/HF, left ventricular end-diastolic dimension (LVEDD), and end-systolic dimension (LVESD) were significantly different in the enalapril group (HF, 8.1 +/- 0.9 to 9.3 +/- 0.9 milliseconds: LF/HF, 1.65 +/- 0.11 to 1.53 +/- 0.16; LVEDD, 57.2 +/- 1.6 to 54.7 +/- 1.6 mm; LVESD, 40.0 +/- 2.4 to 36.3 +/- 1.9 mm) compared with the control group (HF, 8.9 +/- 0.9 to 8.5 +/- 0.7 milliseconds; LF/HF, 1.78 +/- 0.18 to 1.88 +/- 0.15; LVEDD, 52.3 +/- 2.5 to 55.9 +/- 2.2 mm; LVESD, 32.5 +/- 2.6 to 36.1 +/- 2.6 mm; P < .05). The delta change (delta) in LVESD between the end and the start of study correlated inversely with deltaHF (r = -0.56; P < .05) and positively with deltaLF/HF (r = 0.65; P < .01). CONCLUSION: Our results suggest possible ongoing structural changes in patients with old MI even in the absence of overt CHF. Enalapril seemed to prevent such changes and to restore cardiac autonomic tone toward normal. Further prospective studies using a larger sample size are warranted to confirm potential beneficial effects of ACEis in patients with previous MI and preserved left ventricular function.

Aged↗
PubMed1985

Effect of swimming training on cardiac function and myosin ATPase activity in SHR.

Male spontaneously hypertensive rats (SHR) and Wistar-Kyoto normotensive rats (WKY) were subjected to swimming training 6 times/wk, commencing at 4 wk of age, to determine whether this type of endurance exercise might alter contractile proteins and cardiac function in young adult SHR. The total duration of exercise was 190 h. Myofibrillar adenosinetriphosphatase (ATPase) activity was assayed at various free [Ca2+] ranging from 10(-7) to 10(-5) M. Ca2+-stimulated ATPase activity of actomyosin and purified myosin was determined at various Ca2+ concentrations both in the low and high ionic strength buffers. Actin-activated myosin ATPase activity of purified myosin was assayed at several concentrations of actin purified from rabbit skeletal muscle. Under all these conditions the contractile protein ATPase activity was comparable between trained and untrained WKY and SHR. Analysis of myosin isoenzymes on pyrophosphate gels showed a single band corresponding to V1 isoenzyme, and there were no differences between swimming-trained and nontrained WKY and SHR. Ventricular performance was assessed by measuring cardiac output and stroke volume after rapid intravenous volume overloading. Both cardiac index and stroke index were comparable in nontrained WKY and SHR but were significantly increased in the trained groups compared with their respective nontrained controls. These results suggest that myosin ATPase activity and distribution of myosin isoenzymes are not altered in the moderately hypertrophied left ventricle whether the hypertrophy is due to genetic hypertension (SHR) or to exercise training (trained WKY). Moreover, the data indicate that SHR, despite the persistence of a pressure overload, undergo similar increases in left ventricular mass and peak cardiac index after training, as do normotensive WKY.

Adenosine Triphosphatases↗
PubMed1976

Acute cardiac failure: the relation between coronary flow and cardiac function.

To study the effects of acute coronary hypotension on the working dog heart in situ, both coronary arteries were cannulated and perfused with oxygenated blood at controlled pressures (40 to 120 mm Hg). At a perfusion pressure of 120 mm Hg, total coronary artery flow appeared to be sufficient (0.95+/-0.08 ml/min-g) to maintain normal cardiac performance for a 2.5-hour observation period. During incremental decreases in coronary perfusion pressure, significant linear correlations were found between coronary flow and cardiac index (r=0.84), left ventricular maximum dP/dt (r=0.83), stroke index (r=0.82), stroke work (r=0.83) and mean arterial pressure (r=0.62). During simulated shock conditions (systolic arterial pressure, less than 75 mm Hg), relative reductions in coronary flow (-60.9+/-4.0%) paralleled changes seen in cardiac function and persisted for 28+/-4 min.

Animals↗
PubMed2006

Cardiac function and cardiopulmonary performance in patients after treatment for non-Hodgkin's lymphoma.

Authors conducted a one-year prospective study to determine whether CHOP regimen (cyclophosphamide, doxorubicin, vincristin, and prednisone), used in the treatment of aggressive non-Hodgkin s lymphoma, is associated with the presence of an early impairment of cardiac function. Forty seven patients were prospectively examined (27 male and 20 female) aged 49+/-14 years who were treated with CHOP regimen. Rest echocardiography was performed at baseline and one-year control. Cardiopulmonary exercise test was carried out at one-year control examination. The ejection fraction (EF), parameters of diastolic function, myocardial performance index (MPI), and pVO2 were used as parameters of cardiopulmonary performance. The cumulative dose (CD) of doxorubicin was 277+/-56 (300 mg/m(2)) was given. The baseline EF 64+/-5% (64%) decreased to 58+/-7% (57%) at the one-year control (p<0.0001). 23% of patients exhibited a drop in EF >10% during the follow-up. 43% revealed a pathologically increased value of MPI >0.55, and 47% impaired diastolic function compared to the baseline values, respectively. 21% of patients exhibited a decrease of pVO(2) < 20 ml/kg/min, and 17% pVO(2) < 80% of the reference value, respectively. None of the patients developed signs of heart failure. The Doppler parameters of both diastolic and global LV function were the most affected measures and significantly influenced the cardiopulmonary performance. Multivariate analysis showed that CD > or =300 mg/m(2) (OR=8.08; p<0.05) and the presence of risk factors (OR=9.48; p<0.008) are the best predictors of cardiotoxicity. The results show that subclinical cardiac impairment was frequent in patients receiving the CHOP regimen with safe cumulative doses of doxorubicin. The value of described changes for the development of heart failure has to be assessed during the prospective follow-up.

Adolescent↗
PubMed1996

Influence of the low thyroid state in diabetes mellitus on cardiac function and inotropic responsiveness to alpha 1-adrenoceptor stimulation: comparison with the role of hypothyroidism alone.

The hypothyroid state accompanying diabetes mellitus has been suggested to be partly responsible for the diabetes-induced metabolic, hemodynamic, and pharmacological cardiovascular changes. We assessed the effectivity of streptozotocin (STZ) to induce diabetes mellitus and a hypothyroid state. Furthermore, we investigated the influence of diabetes and hypothyrodism on cardiac function and the inotropic responsiveness to the alpha 1-adrenoceptor agonist cirazoline in isolated perfused hearts. Fasted or nonfasted Wistar rats were made diabetic with STZ 20, 40 or 60 mg/kg intravenously (i.v.). Another group was made hypothyroid by addition of 6-n-propyl-2-thiouracil (PTU) to their drinking water. Rats receiving PTU became hypothyroid, whereas rats receiving STZ became simultaneously diabetic and hypothyroid. Basal functional parameters obtained in isolated perfused hearts were not influenced by diabetes, whereas maximal contractility was reduced in hearts obtained from hypothyroid animals. Cardiac inotropic responses to cirazoline were increased in diabetic rats, whereas responses in hypothyroid rats were not different from those in hearts obtained from control animals. Although diabetes mellitus and hypothyroidism are associated with various similar metabolic and haemodynamic parameters, the increased inotropic response to alpha 1-adrenoceptor stimulation as observed in isolated perfused hearts of diabetic rats cannot be explained by the decrease in serum thyroxine levels.

Adrenergic alpha-Agonists↗
PubMed1993

Ro 5-4864 and PK 11195, but not diazepam, depress cardiac function in an isolated working rat heart model.

The present study was designed to investigate the effects of diazepam, a benzodiazepine (BZ) with high affinity to central BZ receptors and moderate affinity to mitochondrial BZ receptors, and of Ro 5-4864 and PK 11195, ligands specific for mitochondrial BZ receptors, on cardiac function in the isolated working rat heart model. Five concentrations of these drugs (10(-9)-10(-5) mol/l) were used, and the chronotropic (heart rate) and inotropic [maximum elastance of the left ventricle at end systole (Emax), maximal first derivative of left ventricular (LV) pressure (dP/dtmax), LV pressure at dP/dtmax (pressure at dP/dtmax), aortic flow, stroke work, and total pressure-volume area] cardiac parameters were measured. Diazepam, Ro 5-4864, and PK 11195 showed no significant chronotropic activity up to 10(-5) mol/l. Diazepam did not alter the inotropic properties of the heart. Ro 5-4864 at 10(-5) mol/l significantly decreased the indices of contractility, namely, Emax, dP/dtmax, and pressure at dP/dtmax. Aortic flow, stroke work, and total pressure-volume area were significantly depressed at the same concentration. The negative inotropism of PK 11195 appeared to be identical, by most indices, to that of Ro 5-4864, both qualitatively (same pattern) and quantitatively (similar maximal variations); however, for some indices a depressant effect was also found at 10(-7) mol/l. These results show that at high concentrations Ro 5-4864 and PK 11195, but not diazepam, have a depressant effect on mechanical function.

Animals↗
PubMed1975

Effects of metrizamide, a new nonionic contrast medium, on cardiac function during coronary angiography in the dog.

Metrizamide is a new non-ionic radiopaque agent with low osmolarity and low intravenous toxicity. Hyperosmolarity is one of the factors involved in the decrease of myocardial contracility, alterations of aortic pressure, and disturbances in the cardiac rhythm which contrast media induce during coronary angiography. Metrizamide has been compared to other commonly used contrast media and was shown to produce fewer changes on the cardiac functions recorded.

Aminoglycosides↗
PubMed1999

Adenovirus-mediated gene transfer of the beta2-adrenergic receptor to donor hearts enhances cardiac function.

Gene transfer to modify donor heart function during transplantation has significant therapeutic implications. Recent studies by our laboratory in transgenic mice have shown that overexpression of beta2-adrenergic receptors (beta2-ARs) leads to significantly enhanced cardiac function. Thus, we investigated the functional consequences of adenovirus-mediated gene transfer of the human beta2-AR in a rat heterotopic heart transplant model. Donor hearts received 1 ml of solution containing 1 x 1010 p.f.u. of adenovirus encoding the beta2-AR or an empty adenovirus as a control. Five days after transplantation, basal left ventricular (LV) pressure was measured using an isolated, isovolumic heart perfusion apparatus. A subset of hearts was stimulated with the beta2-AR agonist, zinterol. Treatment with the beta2-AR virus resulted in global myocardial gene transfer with a six-fold increase in mean beta-AR density which corresponded to a significant increase in basal contractility (LV + dP/dtmax, control: 3152.1 +/- 286 versus beta2-AR, 6250.6* +/- 432.5 mmHg/s; n = 10, *P < 0.02). beta2-AR overexpressing hearts also had higher contractility after zinterol administration compared with control hearts. Our results indicate that myocardial function of the transplanted heart can be enhanced by the adenovirus-mediated delivery of beta2-ARs. Thus, genetic manipulation may offer a novel therapeutic strategy to improve donor heart function in the post- operative setting.

Adenoviridae↗
PubMed2003

Single versus dual chamber pacing in the young: noninvasive comparative evaluation of cardiac function.

The advantages of atrial synchrony over asynchronous ventricular pacing remain unclear in the young, chronically right ventricular (RV) - paced patient. This is in contrast to the older patient with inherent diastolic dysfunction who has been shown to benefit from atrial synchrony with dual chamber (DDD,R/VDD), over single chamber rate response (VVI,R) ventricular pacing. The goal of this study was to noninvasively assess cardiac function in a group of young, RV-paced patients before and after establishment of atrial synchrony. Echocardiographic data were retrospectively analyzed from 10 patients with congenital or acquired complete AV block, who were VVI,R paced for 10.2 +/- 2 years (mean age at study 19.2 +/- 8.9 years), and were subsequently converted to DDD,R/VDD pacing (mean age at study 20.7 +/- 9.5 years). Paired t-test analysis of left ventricular (LV) systolic and diastolic function during VVI,R versus DDD,R/VDD pacing did not result in any short-term difference in LV short axis fractional area of change or FAC (53% +/- 7.5% vs 56.8% +/- 8.7%) or mitral maximal velocity (E) normalized to mitral flow velocity time integral (VTI) (5.2/s +/- 1.5 vs 4.4/s +/- 1.5). A decrease in mitral flow E/A ratio was observed after short-term DDD,R/VDD pacing (2.2 +/- 0.5 vs 1.9 +/- 0.3). Atrial synchronous dual chamber pacing in young patients with complete AV block does not lead to any appreciable early change in global LV function over single-site RV pacing. Therefore, early establishment of atrial synchrony in the young asymptomatic VVI,R-paced patient with normal intrinsic ventricular function may not be warranted.

Adolescent↗
PubMedDate not supplied

Short- and long-term effects of nisoldipine on cardiac function and exercise tolerance in patients with hypertrophic cardiomyopathy.

UNLABELLED: Nisoldipine is a second generation dihydropyridine calcium antagonist having characteristics of strong coronary artery dilating effect and less negative inotropic action. The purpose of this study was to evaluate the effect of nisoldipine on the cardiac function (systolic and diastolic) and the exercise tolerance, in patients with hypertrophic cardiomyopathy (HCM). SUBJECTS: Twenty-three patients with HCM were studied. METHODS: We measured the following indices using M-mode and pulsed wave Doppler echocardiography before and after nisoldipine therapy; left ventricular fractional shortening (LVFS), isometric relaxation time (IRT), deceleration half-time (DHT) of early diastolic mitral (E) flow, late diastolic mitral (A) flow and A/E ratio. Symptom-limited treadmill exercise test was performed. Exercise tolerance (EX) time was measured. Nisoldipine of 10 mg/day was orally administered. Same tests were repeated on day 14 and after 6 months. RESULTS: 1) Short-term effects; LVFS did not change (55.9 +/- 5.9%-->57.0 +/- 7.4%, NS) after 2 weeks. However, LV diastolic function significantly improved (IRT; 92.1 +/- 7.7 ms-->85.2 +/- 11.6 ms, p < 0.05, DHT; 70.7 +/- 16.2 ms-->63.3 +/- 3.7 ms, p < 0.05). EX time increased (8.9 +/- 2.6 min-->10.0 +/- 3.3 min, p < 0.05), 2) Long-term effects; LV diastolic function had a tendency toward improvement, but is statistically not significant (IRT; 91.1 +/- 7.6-->83.8 +/- 11.6 ms, DHT; 73.1 +/- 23.4-->61.0 +/- 11.4 ms, A/E; 1.26 +/- 0.29-->1.11 +/- 0.36) after 6 months. EX time was significantly increased (9.4 +/- 1.7--> 10.1 +/- 1.7 min, p < 0.05). CONCLUSIONS: Nisoldipine improved LV diastolic dysfunction and exercise tolerance in patients with HCM. These effects were similar to the first generation calcium antagonists. LV diastolic dysfunction may be improved due to the reduction of intracellular calcium concentration and the relief of myocardial ischemia by strong coronary artery dilating effect. However, nisoldipine did not affect the LV systolic function because of its less negative inotropic effect.

Adult↗
PubMed1991

[Quantitative study of myocardial pathological lesions in rheumatic mitral valve disease: correlations with changes in cardiac function after valve replacement].

Pathological lesions of left ventricular myocardium from 21 patients with predominant mitral stenosis (MS) and from 16 patients with predominant mitral regurgitation (MI) were studied quantitatively by means of image analysis system and light microscopic examination. Their correlations with changes of cardiac function after mitral valve replacement were also studied. The results showed that the percentage of the area of interstitial fibrosis (F%), the shortest diameter of myocardial fiber (SDMF) and endocardial thickness (ET) increased, and the inner diameter-out diameter ratio of intramyocardial arteries (Di/Do) decreased in 37 patients in various degrees. F%, Di/Do, SDMF and ET correlated with delta EF, delta FS, delta ESVI, postoperative dosage of dopamine, and duration of assisted respiration analysed respectively by linear regression. Multiple myocardial pathological lesions correlated strongly with delta EF analysed by multiple linear regression with multiple correlation coefficient of 0.803 in MS group (P less than 0.01) and 0.763 in MI group (P less than 0.05). These data suggest that multiple evaluation of myocardial pathological lesions plays an important role in predicting prognosis of mitral valve replacement. After operation mean delta EF and delta FS decreased, dosage of dopamine and duration of assisted respiration increased when the patient had two or more following criteria: 1. F% greater than 31%, 2. Di/Do less than 0.400, 3. SDMF greater than 16 microns, 4. ET greater than 326 microns.

Adolescent↗