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J S Child

Publications and source records attributed to J S Child.

At least 37 records · Page 2Linked to original sources
PubMed1993

Impact of left ventricular cavity size on survival in advanced heart failure.

Although left ventricular (LV) dilation has been assumed to be deleterious, the physiologic significance of severe LV dilation in advanced heart failure and its impact on survival have not been defined. LV end-diastolic dimension was measured by M-mode echocardiography in 382 patients with class III or IV heart failure symptoms (mean LV ejection fraction 20 +/- 8%) referred for evaluation for cardiac transplantation. All patients underwent right-sided heart catheterization, and received vasodilator and diuretic therapy adjusted to hemodynamic goals. Although 183 patients with massive LV dilation by LV index > 4 cm/m2 (LV index = LV end-diastolic dimension/estimated body surface area) had a similar severity of hemodynamic impairment to that of 199 patients with only moderate dilation (LV index < or = 4 cm/m2), with baseline mean cardiac index of 2 liters/m/m2 and mean pulmonary arterial wedge pressure of 26 mm Hg in both groups, their actuarial 2-year survival without transplantation was much lower (49 vs 75%; p = 0.004). In the Cox proportional-hazards model, LV index predicted total and sudden death, independent of etiology of heart failure, ejection fraction and other parameters of disease severity. Follow-up echocardiograms (mean 13 +/- 6 months) in 80 heart failure survivors without transplantation showed an increase in mean LV ejection fraction (22 +/- 8% to 26 +/- 13%), but no change in mean LV index in either the massive or moderately dilated groups. Thus, massive LV dilation is an independent contributor to poor outcome in patients with advanced heart failure, and may be stabilized by aggressive vasodilator and diuretic therapy.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1993

Prognostic usefulness of positive or negative exercise stress echocardiography for predicting coronary events in ensuing twelve months.

Stress echocardiography is useful in diagnosing myocardial ischemia in patients with significant coronary artery disease. This study examines the correlation between the results of exercise stress echocardiography and cardiac event rates within 12 months after testing in patients referred for evaluation of possible myocardial ischemia. Cardiac events, defined as myocardial infarction, coronary artery bypass surgery, percutaneous transluminal coronary angioplasty or death, were tabulated for 360 patients with > or = 12 months of follow-up, or a cardiac event within 12 months of follow-up, or both. Wall motion abnormalities at rest were present in 60% of patients. A positive stress echocardiogram, defined as the development of new or worsened wall motion abnormalities, was obtained in 18% of patients (65 of 360), and > or = 1 cardiac event during follow-up was present in 14% (n = 49). A cardiac event occurred in 34% of patients (22 of 65) with a positive stress echocardiogram and in 9% (27 of 295) with a negative one. Myocardial infarctions occurred in 9% of patients with a positive stress echocardiogram compared with 2% with a negative test. An insufficient exercise capacity to reliably exclude ischemia was present in 63% of patients (17 of 27) with a cardiac event despite a negative stress echocardiogram. The predictive value of the stress echocardiographic results was enhanced by combining these results with the electrocardiographic results. In summary, a positive stress echocardiogram was associated with a threefold increased incidence of any cardiac event, and a fourfold increased incidence of myocardial infarction within 12 months of follow-up compared with a negative stress echocardiogram.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Echocardiographic assessment of adults with tetralogy of Fallot.

Advances in medical and surgical management of congenital heart disease in the last three decades have resulted in a great many survivors to adulthood. Proper care requires intimate knowledge of the basic malformations and their surgical anatomy and results. Tetralogy of Fallot, the most common cyanotic malformation in adults, represents a spectrum from mild right ventricular outflow tract obstruction to complete pulmonary atresia. Evaluation of surgical residua and sequelae includes imaging of aortic-to-pulmonary arterial palliative shunts, detection of residual ventricular septal defect patch leaks or right ventricular outflow tract obstruction, definition of extracardiac conduit patency, and quantitation of ventricular function and valvular regurgitation. Refined echocardiographic imaging and hemodynamic definition is a mainstay in precise segmental anatomical and hemodynamic assessment. Transesophageal echocardiography is particularly important for intraoperative evaluation of surgical results.

Adult↗
PubMed1993

Transesophageal echocardiography in congenital heart disease in the adult.

Progress achieved during the last three decades in medical and surgical treatment of infants and children with congenital heart disease has resulted in a significant number of patients surviving to adulthood. The complexity of the basic malformations in addition to the superimposed surgical interventions makes accurate diagnostic imaging essential. The scope of information obtainable from high-quality TEE supports its use in the follow-up of operated and unoperated adult patients, as well as in surgical and interventional procedures. Application of the segmental analysis of anatomy is as important during TEE as it is during TTE. Supplemental transthoracic 2-D and spectral Doppler flow measurements may be needed when poor beam alignment during TEE precludes accurate gradient determinations. Although, to date, most reports of TEE in patients with congenital heart disease have involved children and adolescents, the informational advantage is potentially greater in older adolescents and adults in whom transthoracic windows are frequently limited. In our experience with 125 TEE studies in adult patients with congenital heart disease (the majority using a biplane probe), horizontal plane TEE imaging provided important additional information concerning pulmonary venous connections, atrial baffle function, atrioventricular anatomy and function, left ventricular outflow tract lesions, and great artery positional relationships. Vertical plane TEE enhances imaging of systemic and pulmonary venous connections, atrial situs, venosus atrial septal defects, atrioventricular anatomy and function, and the ventricular septum and outflow tracts and is essential for complete assessment of complex right ventricular outflow tract anatomy, ventriculoarterial alignment, and the sizing of all aortic segments in coarctation of the aorta.

Adult↗
PubMed1992

Stress echocardiographic techniques. An overview.

The choice of upright or supine exercise, pharmacological agents, or atrial pacing for the induction of ischemia depends on the goals and the imaging modality. Dynamic stress echocardiography has improved diagnostic accuracy over and above the stress electrocardiogram. Indications include patients with atypical symptoms, prior nondiagnostic stress electrocardiograms, or baseline electrocardiographic abnormalities. Pharmacological agents coupled with echocardiography do well in the high-risk preoperative patient (e.g., abdominal aneurysmectomy) or in those unable to walk due to orthopedic, neurological, or peripheral vascular disease. When there is uncertainty as to the physiological significance of anatomical (angiographic) stenosis, dynamic stress echocardiography in the ambulatory patient or atrial pacing (or beta-agonist pharmacological stressors) in the catheterization laboratory are useful. The accuracy of stress echocardiography for detection of ischemia in the follow-up of interventional procedures or for postmyocardial infarction risk stratification is superior to standard stress electrocardiography alone.

Adrenergic beta-Agonists↗
PubMed1991

Sustained reduction in valvular regurgitation and atrial volumes with tailored vasodilator therapy in advanced congestive heart failure secondary to dilated (ischemic or idiopathic) cardiomyopathy.

Afterload reduction therapy can acutely improve hemodynamic function in patients with advanced heart failure; however, it is unknown if initial reductions in mitral and tricuspid regurgitation and atrial volumes can be sustained with oral therapy. Atrial volumes and atrioventricular valve regurgitation were measured using 2-dimensional and Doppler echocardiography with color-flow imaging in 14 patients with dilated heart failure (ejection fraction 17 +/- 4%) before and after 3 +/- 1 days of intensive vasodilator and diuretic therapy tailored to hemodynamic goals. Echocardiography was repeated again after 6 +/- 2 months on oral vasodilators and a flexible diuretic regimen. Acute therapy reduced systemic vascular resistance from 1,760 +/- 460 to 1,010 +/- 310 dynes.s.cm-5, pulmonary artery wedge pressure from 30 +/- 5 to 17 +/- 4 mm Hg, and right atrial pressure from 13 +/- 5 to 7 +/- 3 mm Hg, and led to a 61% increase in stroke volume (from 36 +/- 10 to 58 +/- 14 ml) (p less than 0.01). Mitral and tricuspid regurgitation, determined by color-flow fraction, initially decreased from 0.34 +/- 0.17 to 0.20 +/- 0.20 and from 0.33 +/- 0.15 to 0.13 +/- 0.13, respectively (p less than 0.001). This reduction was sustained at 6 months. Significant decreases occurred with acute therapy, with further reductions at 6 months in both mean left atrial volume (from 100 +/- 25 to 80 +/- 19 to 65 +/- 15 cm3) and right atrial volume (from 85 +/- 23 to 64 +/- 23 to 52 +/- 14 cm3) (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1991

Metabolic and functional recovery of ischemic human myocardium after coronary angioplasty.

Although revascularization of hypoperfused but metabolically active human myocardium improves segmental function, the temporal relations among restoration of blood flow, normalization of tissue metabolism and recovery of segmental function have not been determined. To examine the effects of coronary angioplasty on 13 asynergic vascular territories in 12 patients, positron emission tomography and two-dimensional echocardiography were performed before and within 72 h of revascularization. Ten patients underwent late echocardiography (67 +/- 19 days) and eight underwent a late positron emission tomographic study (68 +/- 19 days). The extent and severity of abnormalities of wall motion, perfusion and glucose metabolism were expressed as wall motion scores, perfusion defect scores and perfusion-metabolism mismatch scores. Angioplasty significantly increased mean stenosis cross-sectional area (from 0.95 +/- 0.9 to 2.7 +/- 1.4 mm2) and mean cross-sectional luminal diameter (from 0.9 +/- 0.6 to 1.9 +/- 0.5 mm) (both p less than 0.001). Perfusion defect scores in dependent vascular territories improved early after angioplasty (from 116 +/- 166 to 31 +/- 51, p less than 0.002) with no further improvement on the late follow-up study. The mean perfusion-metabolism mismatch score decreased from 159 +/- 175 to 65 +/- 117 early after angioplasty (p less than 0.01) and to 26 +/- 29 at late follow-up (p less than 0.001 vs. before angioplasty; p = NS vs. early after angioplasty). However, absolute rates of glucose utilization remained elevated early after revascularization, normalizing only at late follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1991

Use of echocardiography for patient management in chronic ischemic heart disease.

Myocardial ischemia causes regional myocardial contractile and relaxation abnormalities. The extent of ischemia is determined by the distribution and severity of coronary artery stenoses. In coronary heart disease, two powerful predictors of prognosis are the coronary anatomy and ventricular function. Management in coronary heart disease is directed by accurate diagnosis and individualized objectives. Echocardiography at rest and exercise, combined with Doppler and color flow imaging, are properly applied to the differential diagnosis of common clinical syndromes in ischemic heart disease, the identification of the proximal coronary arteries, and the effects of ischemia and prior infarction. Subsequent use of coronary arteriography partially depends on the philosophy regarding the applicability of coronary surgery or angioplasty in an individual patient. Prediction of multivessel, left main, or proximal left anterior descending coronary artery disease by extensive wall motion abnormalities or an abnormal left ventricular ejection fraction may direct the clinician to coronary arteriography to select among coronary surgery, angioplasty, or medical management.

Algorithms↗
PubMed1991

Cardiac preservation in patients undergoing transplantation. A clinical trial comparing University of Wisconsin solution and Stanford solution.

Recent laboratory investigations have shown significantly improved donor heart preservation and function when the University of Wisconsin solution (UW) is used for arrest and storage. These findings prompted us to compare UW to Stanford solution in a clinical trial. After giving informed consent, patients were blindly randomized to receive a heart arrested and stored in UW or a heart arrested in Stanford solution and stored in normal saline. Orthotopic transplants were performed in a routine manner. Fourteen patients with a mean age of 54 years were randomized to UW, and 15 patients with a mean age of 51 years were randomized to Stanford solution. Mean donor ages (UW 27 years, Stanford 24 years) and ischemic times (UW 150 minutes, Stanford 135 minutes) were similar. Several differences were observed intraoperatively. At end ischemia, mean adenosine triphosphate (UW 5.87 mmol/gm wet weight, Stanford 4.75 mmol/gm) and creatine phosphate (UW 9.26 mmol/gm, Stanford 4.75 mmol/gm) levels were higher in the UW hearts (p less than 0.05). Defibrillation requirements (UW 14% [2/14], Stanford 53% [8/15]) were significantly less in the UW group (p = 0.05). The number of patients requiring temporary intraoperative pacing also showed a significant difference with 7% (1/14) of UW patients versus 47% (7/15) of Stanford patients requiring pacing (p less than 0.05). Intraoperative requirement for inotropic support showed a trend in favor of the UW group. End-ischemic and postreperfusion histologic characteristics were similar between the two groups. No differences in hemodynamics or ejection fractions were noted postoperatively, but trends toward improved rhythm and decreased inotropic support were present in the UW group. Overall 6-month survival rates were similar (UW 86% [12/14], Stanford 93% [14/15]). No preservation-related deaths occurred. We conclude: (1) UW is a safe and effective preservation solution for human cardiac transplantation; (2) considering the improved end-ischemic adenosine triphosphate and creatine phosphate levels, decreased defibrillations, decreased intraoperative pacing, and trend toward decreased requirement for inotropic support in the UW group, UW appears to be superior to Stanford solution for donor heart preservation.

Adenosine Triphosphate↗
PubMed1990

Acute reduction of atrial overload during vasodilator and diuretic therapy in advanced congestive heart failure.

Although acute afterload reduction is known to improve cardiac output in patients with congestive heart failure (CHF), the effect of therapy on the atrial overload directly causing congestive symptoms has not been systematically studied. Atrial volumes and mitral and tricuspid regurgitation, in addition to left ventricular ejection fraction and indexes of left ventricular contractility (mean acceleration, ejection time and peak systolic pressure/end-systolic volume index), were measured using 2-dimensional and Doppler echocardiography and color flow imaging in 30 patients with advanced CHF, before and after acute vasodilator and diuretic therapy tailored to hemodynamic goals. Therapy increased stroke volume by 64% (36 +/- 10 to 55 +/- 14 cc), decreased right atrial pressure by 45% (15 +/- 5 to 8 +/- 4 mm Hg), systemic vascular resistance by 36% (1,700 +/- 400 to 1,030 +/- 300 dynes s cm-5) and pulmonary capillary wedge pressure by 37% (31 +/- 6 to 19 +/- 6 mm Hg) (all p less than 0.001). Echocardiography showed simultaneous reductions in left and right atrial volumes: 24 +/- 19 and 18 +/- 12%, respectively (p less than 0.001). Mitral and tricuspid regurgitation measured by color flow fraction both decreased by a mean of 44% (p less than 0.001). While ejection fraction increased from 15 +/- 5 to 19 +/- 7% (p less than 0.001), there were no changes in relatively load-independent indexes of contractility. Therefore, acute therapy with vasodilators and diuretics in advanced CHF causes reductions in atrial volumes and atrioventricular valve regurgitation that are evident from serial noninvasive studies and may play a major role in the improvement of congestive symptoms.

Adolescent↗
PubMed1990

Echo-Doppler and color-flow imaging in congenital heart disease.

Enormous strides in diagnosis and management have allowed many patients with congenital heart disease to reach adulthood. Proper care of these individuals requires knowledge of the anatomic and hemodynamic faults of the original defect, the dynamic changes that occur with time, and the effects of adult diseases or surgical intervention on that physiology. Echocardiographic and Doppler assessment of these patients has revolutionized their management. This article has discussed individual abnormalities such as shunts, obstructive or regurgitant lesions, and great-vessel and chamber malpositions, as well as selective aspects of more complex malformations. In the patient with congenital heart disease, whether unoperated or postoperative, a complete echo-Doppler examination includes complete anatomic delineation of intra- and extracardiac structures using combined two-dimensional and color-flow imaging, assessment of chamber sizes and myocardial function, and complementary pulsed and continuous-wave Doppler and color-flow imaging to search for and quantitate valvular, subvalvular or supravalvular stenosis or regurgitation; extra- and intracardiac conduit stenosis; pulmonary and systemic venous obstruction; transseptal or patch shunts; and intracardiac hemodynamics.

Adolescent↗