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PubMed1986

Evaluation of hypertrophic cardiomyopathy by Doppler color flow imaging: initial observations.

We evaluated hypertrophic cardiomyopathy in 12 patients by Doppler color flow imaging and continuous-wave Doppler echocardiography. Mitral regurgitation was detected by continuous-wave Doppler echocardiography in eight patients and was related to the degree of systolic anterior motion of the mitral valve. Adequate color flow images were obtained in 10 of the 12 patients, and mitral regurgitation was demonstrated in 6. A qualitative and quantitative analysis of the color flow imaging revealed a temporal pattern in the left ventricular outflow tract that consisted of normal-velocity laminar flow during early systole followed by turbulent flow in midsystole. The maximal amount of mitral regurgitation on color flow imaging occurred late in systole, after the appearance of turbulent flow in the left ventricular outflow tract. Of the 12 patients, 10 had late-peaking continuous-wave Doppler velocity profiles in the left ventricular outflow tract. The peak velocity detected in the left ventricular outflow tract was positively correlated with the degree of systolic anterior motion of the mitral valve. Patients with higher peak velocities in the left ventricular outflow tract had prolonged ejection times. These findings on Doppler echocardiography support the concept of left ventricular outflow obstruction in some patients with hypertrophic cardiomyopathy.

Adult↗
PubMed1984

Primary right ventricular tumor (fibroma) simulating cyanotic heart disease in a newborn.

The clinical, echocardiographic, cineangiocardiographic and autopsy findings in a newborn infant with right ventricular fibroma are reported. The tumor caused severe right ventricular outflow obstruction simulating cyanotic heart disease. Echocardiography allowed a definitive diagnosis of the tumor mass at 10 hours of age. The clinical implications of the case are discussed.

Cineangiography↗
PubMed1987

Noninvasive assessment of left ventricular diastolic function by pulsed Doppler echocardiography in patients with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy is a primary myocardial disease in which symptoms may frequently result from impaired left ventricular relaxation, filling and compliance. In the present investigation, Doppler echocardiography was utilized to measure transmitral flow velocity and thereby assess left ventricular diastolic performance noninvasively in a group of 111 patients representative of the broad clinical spectrum of hypertrophic cardiomyopathy. In patients with hypertrophic cardiomyopathy, all Doppler indexes of diastolic relaxation and filling differed significantly (p less than 0.001) from those obtained in 86 control subjects without heart disease, namely, prolongation of isovolumic relaxation (94 +/- 24 versus 78 +/- 12 ms) and of the early diastolic peak of flow velocity (244 +/- 55 versus 220 +/- 28 ms), as well as slower deceleration (3.4 +/- 1.4 versus 4.9 +/- 1.3 m/s2) and reduced maximal flow velocity in early diastole (0.5 +/- 0.2 versus 0.6 +/- 0.1 m/s). As an apparent compensation for impaired relaxation and early diastolic filling, the atrial contribution to left ventricular filling was increased, as shown by increased late diastolic flow velocity (0.4 +/- 0.3 versus 0.3 +/- 0.1 m/s) and reduced ratio of maximal flow velocity in early diastole to that in late diastole (1.4 +/- 0.8 versus 2.1 +/- 0.9). The vast majority of patients with hypertrophic cardiomyopathy (91 [82%] of 111) showed evidence of impaired left ventricular diastolic performance, as assessed from the Doppler waveform. Abnormal Doppler diastolic indexes were identified with similar frequency in patients with (78%) or without (83%) left ventricular outflow obstruction, as well as in patients with (84%) or without (80%) cardiac symptoms. However, patients with nonobstructive hypertrophic cardiomyopathy showed more severe alterations in the Doppler indexes of diastolic function than did patients with obstruction. Thus, abnormal diastolic performance as assessed by Doppler echocardiography was apparent in the vast majority of the study patients with hypertrophic cardiomyopathy, independent of the presence or absence of cardiac symptoms or a subaortic pressure gradient. The high frequency with which diastolic abnormalities are identified in asymptomatic patients with hypertrophic cardiomyopathy suggests that impaired diastolic performance may be present at a time in the natural history of the disease when functional limitation is not yet evident.

Adolescent↗
PubMedDate not supplied

Echocardiographic and Doppler assessment of hypertrophic cardiomyopathy.

Echocardiographic and Doppler studies are invaluable in the detection and management of patients with hypertrophic cardiomyopathy, since virtually all aspects of the disorder can be evaluated. Echocardiography is the primary method of diagnosis, and hemodynamic studies are required usually only when surgery is contemplated. All patients should if possible undergo complete M-mode, two-dimensional, Doppler, and color flow studies to define the extent of hypertrophy, the hemodynamic subgroup, quantitation of left ventricular outflow obstruction, mitral regurgitation when present, and an assessment of diastolic function. Patients undergoing medical or surgical therapy for this disorder should have repeat studies performed to assess the effects of therapy on the degree of obstruction and diastolic dysfunction.

Cardiomyopathy, Hypertrophic↗
PubMed2001

Surgical management and indication of left ventricular retraining in arterial switch for transposition of the great arteries with intact ventricular septum.

OBJECTIVE: Arterial switch is the operation of reference for the surgical treatment of transposition of the great arteries. In cases of late referral, perinatal complications or early left ventricular (LV) dysfunction, the one stage arterial switch is contra indicated. Anatomical repair remains possible in these patients following a LV retraining. METHODS: From January 1992 to January 2000, a LV retraining was attempted in 22 patients with transposition of the great arteries with intact ventricular septum (TGA IVS), whereas 470 direct arterial switch and 2 Senning were performed. Indication for LV retraining was based on a combination of factors including: an age older than 3 weeks, a "banana shape" aspect of the inter-ventricular septum and mainly a LV mass <35G/m(2). RESULTS: The mean age at LV retraining was 3.2 months ranging from 9 days to 8 months. Usually conducted by sterntomy, it associated a loose PA banding with a LV/RV at 65% with a systemico-pulmonary shunt. The first stage was associated with frequent LV dysfunction and the LV retraining was discontinued in two patients in favor of one Senning and one early switch followed by ECMO. One patient died at first stage from a mediastinitis. Nineteen patients underwent a second stage arterial switch that was performed when the LV mass had reached 50 G/m(2) after a mean delay of 10 days, ranging from 5 days to 6 weeks. After a mean follow up of 25 months, there was one non-cardiac late death. The 17 patients followed and leaving with an arterial switch are in NYHA class I, with a mean LV shortening fraction of 39%. CONCLUSIONS: Arterial switch following LV retraining in TGA IVS is a satisfactory option. The inferior limit of 35 G/m(2) adopted, to indicate LV retraining, seems a safe landmark. The quality of the myocardium generated and the respective roles played by the LV afterload, LV wall shear stress, LV inflow and outflow to induce the LV remodeling remain under debate.

Child↗
PubMed1999

Progression of congenital heart disease in the prenatal period.

BACKGROUND: Prenatal echocardiography has shown evidence of prenatal development of congenital heart disease. Prenatal cardiac anatomy, chamber size and function change during gestation, so that the appearance of cardiac structure in abnormal hearts may be different from that which is usually seen postnatally. METHODS: Published prenatal echocardiographic studies were reviewed and in utero development of congenital heart disease from midtrimester to the early postnatal period is discussed. RESULTS: The growth of the great vessels and ventricles is reduced in fetuses with ventricular outflow obstruction. Valve regurgitation may progress. The foramen ovale and ductus arteriosus have been reported to become restrictive in utero in several settings. Pulmonary vascular obstructive changes may progress prenatally. Fetal arrhythmia (both bradycardia and tachycardia) may develop in utero. Development of congestive heart failure is a very important issue during follow up of fetuses with significant cardiac or extracardiac problems. Some may progress to fetal hydrops and prognosis of the affected fetuses is usually very poor. CONCLUSIONS: Correct knowledge of possible development is important for accurate prenatal diagnosis. Information on prenatal progression of the cardiac anomaly is also important to make plans for follow up and perinatal management, to predict outcomes and to counsel family. Furthermore, the benefits of prenatal treatment instead of postnatal treatment should be assessed by the accurate prediction of the progression of the cardiac problem in utero. Further extensive studies using a large number of cases is required to predict progression accurately. In addition, further studies for elucidating the mechanisms of progression is important to provide better outcomes for fetuses with various congenital heart diseases.

Arrhythmias, Cardiac↗
PubMed2001

Clinical usefulness of a multielectrode basket catheter for idiopathic ventricular tachycardia originating from right ventricular outflow tract.

INTRODUCTION: It often is difficult to determine the optimal ablation site for idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) when the VT or premature ventricular complex (PVC) does not occur frequently. The aim of our study was to evaluate the usefulness of a multielectrode basket catheter for ablation of idiopathic VT originating from the RVOT. METHODS AND RESULTS: Radiofrequency (RF) catheter ablation was performed using a 4-mm tip, quadripolar catheter in 50 consecutive patients with 81 VTs originating from the RVOT with (basket group = 25 patients with 45 VTs) or without (control group = 25 patients with 36 VTs) predeployment of a multielectrode basket catheter composed of 64 electrodes. Deployment of the multielectrode basket catheter was possible and safe in all 25 patients in the basket group. Ablation was successful in 25 (100%) of 25 patients in the basket group and in 22 (88%) of 25 patients in the control group. The total number of RF applications and the number of RF applications per PVC morphology did not differ between the two groups. However, both the fluoroscopic and ablation procedure times per PVC morphology were shorter in the basket group than in the control group (36.8+/-14.1 min vs 52.0+/-32.5 min, P = 0.04; 60.0+/-14.6 vs 81.5+/-51.2 min, P = 0.05). This difference was more pronounced in the 29 patients in whom VT or PVC was not frequently observed. CONCLUSION: The multielectrode basket catheter is safe and useful for determining the optimal ablation site in patients with idiopathic VT originating from the RVOT, especially in those without frequent VT or PVC.

Activation Analysis↗
PubMed1979

Right-to-left atrial shunt in cardiac dislocation following extensive pneumonectomy.

Previous reports dealing with cardiac herniation following intrapericardial pneumonectomy illustrate the critical and often lethal hemodynamic sequelae of this complication. In the case presented here, the first and nearly exclusive sign of cardiac herniation after left-sided pneumonectomy with extensive resection of the pericardium was systemic arterial hypoxemia. Subsequent investigations suggested inter-atrial right-to-left shunt in the presence of a patent foramen ovale, caused by slight right-ventricular outflow obstruction with consecutively reversed pressure relationships at atrial level. This explanation was supported by the operative findings, and reversibility was achieved by pericardial reconstruction with parietal pleura. When the patient died 8 months later due to general progression of a mucoepidermoid carcinoma, autopsy confirmed a large patent foramen ovale.

Adenocarcinoma, Mucinous↗
PubMed1998

Cardiac metastasis of a malignant fibrous histiocytoma occupying the right ventricle and infiltrating the myocardium.

A 86-year-old woman presented with a cardiac tumor occupying the whole cavity of the right ventricle and causing right ventricular outflow obstruction. A percutaneous ultrasound-guided biopsy was performed and histologic examination revealed a metastasis of a malignant fibrous histiocytoma. Because of the extensive cardiac involvement and multiple pulmonary metastases, effective surgical therapy was not possible and the patient died soon after diagnosis.

Aged↗
PubMed1991

Cardiovascular causes of syncope. Identifying and controlling trigger mechanisms.

Syncope usually has a cardiovascular source, so neurologic evaluation has a low diagnostic yield in these patients. Cardiac arrhythmias in persons with or without structural heart disease can produce syncope. Neurocardiogenic dysfunction that results in diminished venous return and hypercontractility is another frequent cause. Postural hypotension or left ventricular outflow obstruction may also be to blame. Careful history taking and physical examination, head-up tilt testing, echocardiography or radionuclide isotope imaging, and electrophysiologic study are often diagnostic. However, syncope remains undiagnosed in some patients, and they may require periodic reassessment. Treatment options are available for most cardiovascular disorders, among them use of pharmacologic agents; catheter, surgical, or radio-frequency modification of certain tachycardias; and permanent pacing.

Cardiac Pacing, Artificial↗
PubMed2002

Continuous on-line measurement of absolute left ventricular volume by transcardiac conductance: angiographic validation in sheep.

OBJECTIVE: Validation of the transcardiac conductance method for continuous, on-line measurement of absolute left ventricular volume by comparison with biplane angiography. DESIGN: Controlled, prospective animal study. SETTING: Catheterization laboratory of the Leiden University Medical Center. SUBJECTS: Six anesthetized sheep. INTERVENTIONS: Subjects were studied at baseline, during infusion of dobutamine, and during volume loading and beta blockade. In a pilot experiment, a coronary artery was occluded by a balloon, and the behavior of the transcardiac conductance signals during ischemia was tested. MEASUREMENTS AND MAIN RESULTS: Calibration factors alpha and V(p) were determined by thermodilution and hypertonic saline dilution, respectively. Calibrated transcardiac conductance volume was compared with angiographic volume in four different hemodynamic conditions, and transcardiac conductance measurements were registered during a period of ischemia. Results showed a good linear correlation between transcardiac conductance and angiographic volume (r =.77, p <.01) with an intercept of 12.5 +/- 5.6 mL (interanimal variability, 17.8 mL) and a slope of 1.49 +/- 0.15 (interanimal variability, 0.34). Mean alpha and V(p) were 0.12 +/- 0.01 (interanimal variability, 0.07) and 104 +/- 3 mL (interanimal variability, 38 mL), respectively. V(p) did not vary significantly between conditions, and alpha varied only during propranolol (p =.04). Transcardiac conductance enabled immediate visualization of acute left ventricular volume changes during coronary occlusion in a pilot experiment. CONCLUSIONS: Transcardiac conductance is a method to register an on-line, continuous, left ventricular volume signal, which correlates well with angiography. However, calibration factors need to be determined in individual subjects. The method appears promising to monitor absolute volume in the intensive care unit.

Angiography↗
PubMed2005

Management of pediatric hypertrophic cardiomyopathy.

PURPOSE OF REVIEW: As the underlying genetic basis of hypertrophic cardiomyopathy is being characterized, there has been increasing recognition of the wide spectrum and variable evolution of this disease within the pediatric age range. This review outlines recent evidence relevant to the diagnosis, management, and prognosis of hypertrophic cardiomyopathy specific to children and adolescents. RECENT FINDINGS: Studies of putative causal genes are leading to the discovery of factors affecting the variability of phenotypic expression and possible avenues for new therapies. Nonetheless, the use of genetic testing currently remains for research purposes only. Echocardiography is the primary means for evaluation, with an increasing focus on diastolic performance. Useful prognostic information can be obtained from the safe performance of cardiopulmonary stress testing. Sudden death can occur in children, although the risk factors are likely different than in adults. The role and mechanisms for possible ischemia remain controversial, and likely differ between individuals. Activity restrictions are recommended, with medical therapy reserved for those who are symptomatic. For those with important left ventricular outflow obstruction, surgical myectomy may be indicated, with little current role for alcohol septal ablation. Advances in implantable defibrillators now make this therapy feasible in younger children. SUMMARY: There are important differences from adults in the approach to the diagnosis and management of hypertrophic cardiomyopathy in children and adolescents. Care regarding prognostication and therapy must be taken given the potential life-long implications.

Cardiomyopathy, Hypertrophic, Familial↗
PubMed1990

Cardiovascular reflexes from cardiac sensory receptors.

The mammalian heart, especially its left ventricle, is densely innervated by sensory nerves. One set of these travels to the brainstem in the vagus nerves; the other to the spinal cord in sympathetic nerves. Excitation of vagal cardiac afferents, especially unmyelinated afferents from the left ventricle, cause a reflex bradycardia and fall in blood pressure and, under some conditions, a massive release of AVP. The sympathetic afferents convey the sensation of cardiac pain, but innocuous stimuli may cause a reflex tachycardia and rise in blood pressure. Both sympathetic and vagal cardiac afferents can be excited by mechanical distension of the heart (mechanoreceptors), and by a variety of foreign and endogenous chemical substances (chemosensitive receptors). It is not yet clear whether the effective natural stimulus to these receptors is mechanical, or through the chemical products of myocardial metabolism. Neither is it clear whether information from the heart exerts a minute-to-minute regulatory effect on the circulation, or whether it has a purely defensive role in the face of extreme disturbances of cardiac function. Cardiogenic reflexes are also thought to be the cause of haemodynamic and humoral disturbances that occur in clinical conditions such as myocardial ischaemia or infarction, left ventricular outflow obstruction, and acute reduction in central blood volume as well as during coronary angiography.

Afferent Pathways↗
PubMed1994

Radiofrequency catheter atrioventricular node ablation in patients with permanent cardiac pacing systems.

Following successful RF ablation of the atrioventricular node (AVN), temporary pacing is necessary prior to insertion of a permanent pacemaker. The risks and inconvenience of temporary pacing could be avoided if a permanent pacemaker is already in place. This study reports the feasibility of RF ablation of the AVN in 27 patients (age 55 +/- 17 years, 15 males) with hypertrophic cardiomyopathy and pacemakers. Indications for AVN ablation were drug refractory atrial fibrillation in 24 patients, and rapid AVN conduction preventing septal pre-excitation by DDD pacemaker, inserted for relief of left ventricular outflow obstruction, in three cases. Sixteen patients had DDD devices and 11 patients had VVI devices. During RF ablation, each pacemaker was programmed to VVI at 50 beats/min. The ablation catheter was manipulated with fluoroscopic control to avoid close contact with or disturbance of the pacing leads. In 16 patients, RF ablation was performed immediately following pacemaker implantation but in the remaining patients, the AVN was ablated 6-32 months after pacemaker implantation. The power applied was 25-50 watts for a duration of 15-60 seconds. AV block was achieved in all cases but required 34 +/- 36 applications for 16.5 +/- 17.8 min/case. RF ablation consistently caused reversion to magnet rate in one patient and temporarily inhibited appropriate pacemaker discharge in another. However, no other pacemaker or lead malfunction was detected so that temporary pacing was not required in any case. At 6 +/- 3 months follow-up, all pacemakers were functioning normally without alteration in pacing parameters from baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2004

Dynamics of T-U wave in patients with idiopathic ventricular tachycardia originating from the right ventricular outflow tract.

Postextrasystolic U wave augmentation is observed in patients with long QT syndrome and those with organic heart disease. This phenomenon is considered a marker of increased risk of arrhythmia. However, the characteristics of the U wave have not been evaluated in patients with idiopathic VT originating from the right ventricular outflow tract (RVOT-VT). The present study evaluated the dynamic change in the T-U wave in patients with RVOT-VT. Holter ECGs obtained from 14 patients with RVOT-VT and 11 healthy control subjects were analyzed. The amplitude of T and U waves (Tamp and Uamp) and preceding RR intervals were measured during stable sinus rhythm (rate dependent change) and in the postextrasystolic sinus complex (pause dependent change). Uamp correlated negatively and significantly with the preceding RR interval in 13 (93%) RVOT-VT patients but in only 2 (18%) control subjects. The average value of the slope of the Uamp/RR relationship was negative (-0.22 +/- 0.10 mV/s) in the RVOT-VT group, but was positive (0.04 +/- 0.07 mV/s, P < 0.001) in the control group. Pause dependent U wave augmentation was observed in 12 (86%) of 14 patients. Increased frequency of consecutive preceding premature ventricular contractions (PVCs) was associated with a larger postextrasystolic Uamp. PVC or the first ventricular beat of VT arose from near the peak of augmented U waves. The dynamic changes in the T-U wave were observed in patients with RVOT-VT. Further investigations are required to elucidate the precise role of the U wave in arrhythmogenesis in those patients.

Adult↗
PubMed1989

Echocardiographic assessment of infants born to diabetic mothers.

Echocardiography was carried out in 31 neonates (group 1) born to diabetic mothers and 37 control infants (group 2) matched for weight and gestational age. The interventricular septum was significantly thicker in group 1 babies (mean (SD) 4.77 (1.4) mm) compared with those in group 2 (2.5 (0.7) mm); in eight it was more than 5 mm, but had regressed in six over a period of three months. There was no significant difference between the two groups in the left ventricular internal dimension, right ventricular outflow tract, or size of the left atrium or the aorta. The left ventricular mass was significantly greater in infants born to diabetic mothers. The left ventricular contractility (judged by the percentage of shortening of the internal dimension and the ejection fraction) was significantly greater in group 1. No evidence of left ventricular outflow obstruction was found on pulse Doppler echocardiography in group 1.

Cardiomyopathy, Hypertrophic↗
PubMed1975

Pulmonary valve echo motion in pulmonary regurgitation.

Four cases are presented to illustrate the echo patterns of pulmonary valve motion in patients with pulmonary regurgitation caused by pulmonary hypertension, idiopathic dilatation of the pulmonary artery, or congenital absence of the pulmonary valve or in association with pulmonary stenosis. Absence of the pulmonary 'a' wave, fluttering of the e-f slope, and midsystolic closure or 'notching' of the valve were noted with pulmonary hypertension. In the case with idiopathic dilatation of the pulmonary artery a normal echo pattern of pulmonary valve motion along with distinct dilatation of the pulmonary artery at the valvular level were present. Pronounced dilatation and systolic expansion of the pulmonary artery along with dilatation of the right ventricle were seen with congenital absence of the pulmonary valve. No pulmonary valve could be demonstrated on multiple scans from the right ventricle to pulmonary artery. In Case 4 large 'a' waves (14 mm) were noted, indicating a reversal of the normal end-diastolic gradient across the valve and suggesting that pulmonary regurgitation in this case was associated with right ventricular outflow obstruction. Study of the echo pattern of pulmonary valve motion may therefore provide useful information in establishing the cause of pulmonary regurgitation.

Adolescent↗