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The hemodynamic effects of prenalterol, a parenteral cardioselective beta 1-receptor agonist, were evaluated by cardiac catheterization in patients with refractory severe congestive heart failure (CHF). Prenalterol (PN) (4 mg i.v.) did not alter (p greater than 0.05) heart rate (HR), mean blood pressure (MBP) or left ventricular filling pressure (LVFP). Concomitantly PN markedly augmented cardiac index (CI) from 1.9 to 2.6 l/min/m2 (p less than 0.01) and substantially elevated stroke index (SI) from 24 to 30 ml/beta/m2 (p less than 0.001). In addition PN raised stroke work index (SWI) from 21 to 26 g . m/m2 (p less than 0.005) and decreased total systemic vascular resistance (TSVR) from 1702 to 1260 dyn . s. cm-5 (p less than 0.001). An important finding was that the heart rate x systolic blood pressure product was unchanged (p greater than 0.05) and precipitation of cardiac dysrhythmias or myocardial ischemia were not observed. Further PN 1 mg, 4 mg and 8 mg i.v. was sequentially injected and peak hemodynamic effects were determined 10 min after drug administration. PN 1 mg raised CI from 2.1 to 2.5 1/min/m2 (p less than 0.01), elevated SI from 24 to 29 ml/beat/m2 (p less than 0.01), and augmented SWI from 21 to 25 g . m/m2 (p less than 0.01), however, TSVR declined from 1702 to 1392 dyn . s. cm-5. Subsequent incremental PN doses of 4 and 8 mg did not provide (p greater than 0.05) additional enhancement of cardiac function. Thus, prenalterol produced markedly beneficial enhancement of cardiocirculatory function without untoward effects and may be useful in the management of patients with severe congestive heart failure. Moreover, dose-response analysis indicates these salutary improvements can be maximally produced by the small dose of 1 mg obviating the need for larger doses.

Bedside right heart catheterization in patients with acute myocardial infarction and hemodynamic dysfunction provides a rational basis for therapy aimed at maximizing cardiac performance and limiting infarct size. Readily performed and associated with minimal risk, this diagnostic approach is primarily indicated when myocardial infarction is associated with evidence of hemodynamic dysfunction. It affords precise information on cardiac performance and prognosis, allows identification of specific complications such as ventricular septal defect and acute mitral regurgitation, and is of critical importance in selection of therapy. Hemodynamic monitoring is also essential for safe, effective application of certain forms of treatment such as vasodilator therapy for the failing ventricle.

To provide more effective vasodilator agents for the therapy of severe left ventricular (LV) failure the cardiocirculatory actions of prostaglandin E1 (PGE1) were evaluated in nine coronary patients. PGE1 infusion modestly decreased mean systemic blood pressure (85 to 76 mm Hg, p less than 0.025) and LV filling pressure (19 to 15 mm Hg, p less than 0.01) while heart rate was unchanged (p less than 0.05). Simultaneously, PGE1 augmented cardiac index from 1.9 to 2.5 1/min/m2 (p less than 0.005), raised stroke index from 28 to 35 ml/beat m2 (p less than 0.01) and increased stroke work index from 26 to 30 g-m/m2 (p less than 0.02). Additionally, total systemic vascular resistance decreased from 1862 to 1282 dynes-sec-cm-5 (p less than 0.02) and double product of heart rate and systolic blood pressure diminished from 9492 to 8278 mm Hg (p less than 0.02) while the effective endocardial perfusion pressure was maintained (p less than 0.05). Concomitantly, forearm vascular resistance fell, forearm blood flow was raised, and forearm venous tone remained unchanged. Thus, our results demonstrate that PGE2 is a potent arteriolar vasodilator with markedly beneficial effects of myocardial energetics and on cardiac function in patients with severe ischemic congestive cardiac failure.

ACEIs are widely prescribed antihypertensives and have become the mainstay of therapy for severe CHF. Nevertheless, a focused AII-receptor blockade has compelling intellectual appeal and substantial clinical advantages over the ACEIs (no disruption of the prostaglandin and bradykinin biosystems). Identification and careful characterization of the AII receptors and the recent discovery of their antagonists has led to the extensive clinical investigation of selective AII-receptor blockers in both hypertension and severe CHF. Studies with the first orally active AII-receptor blocker, losartan, have demonstrated safe and effective control of elevated blood pressure and improvement of the abnormal hemodynamics typical of pronounced CHF. Several other oral AII-receptor blockers are currently being evaluated, and early results with these agents are encouraging.

tth the initial demonstration of laser in corow nary artery disease,‘,* several experimental animal and clinical studies have been conducted in the past decade to determine the potential of coronary laser angioplasty. The principal impetus for the laser as well as for all other non-balloon interventional devices is to combat the severe sequelae following percutaneous transluminal balloon angioplasty (BTCA), namely restenosis. Early clinical investigations involved using continuous-wave lasers such as argon or neodymium: yttrium-aluminum-garnet (YAG) transmitted via a silica fiber and exiting the tip as a free beam3 or heating a metal probe.4 These lasers and laser-heated probes not only effect thermal damage to the obstructed site but also its adjacent area, including the vessel wall. Such effects have caused concerns that continuous-wave lasers would potentially increase the frequency of coronary spasm, vessel thrombosis, and luminal wall injury such as dissection, aneurysm and perforation.5*6 The extimer laser, however, is a pulsed laser, and is believed to be more ideal for excimer coronary laser angioplasty (ECLA) because it ablates atherosclerotic plaque ob struction by a nonthermal mechanism,7 thus anticipating lower complication and restenosis rates. This communication examines whether present excimer laser systems have achieved the potential of safe and effective coronary angioplasty. Excimerlauwsad ewonary delivery systems: The excimer laser is comprised of a gas as its lasing medium. There are 4 excimer gases each of which produces a different ultraviolet wavelength (i.e., argon fluoride 193 nm, krypton fluoride 248 nm, xenon chloride 308 nm, and xenon fluoride 351 nm). Excimer stands for “excited dimer” and connotes 2 atoms in an excited state in the lasing medium. ECLA cannot take advantage of the shorter ultraviolet wavelengths (e.g., 193 and 248 nm) because it cannot be transmitted down a silica fiber (transmission range from 300 to 2,100 nm). The xenon chloride excimer laser (308 nm) is mostly utilized in angioplasty investigations and is generally operated between 100 and 250 mJ at 20 to 40 Hz. However, the pulse energy of the xenon chloride light has to be modified by prolonging the pulse width and thereby reducing peak power per pulse in order to conduct the energy through a silica fiber without damage to the fiber. Thus, the limitation of present fiberoptic delivery system has affected the use of the full capability of the excimer laser.

Both angiotensin II and the protein kinase C activator, phorbol 12-myristate 13-acetate (PMA), significantly depressed developed pressure, oxygen consumption, and coronary flow in isolated perfused rat hearts and caused a decrease in diastolic and systolic [Ca 2+ ] i and [Ca 2+ ] i transients. PMA and angiotensin II did not change the levels of cAMP but moderately decreased PCrCr. The decrease in systolic [Ca 2+ ] i and amplitude of [Ca 2+ ] i transients caused by PMA and angiotensin II resulted in depressed cardiac function. Hearts perfused with PMA and angiotensin II had a decreased sensitivity to extracellular calcium. Depressed developed pressure and oxygen consumption in the PMA- and angiotensin II-treated hearts may have been due to a decrease in amplitude of effective [Ca 2+ ] i transients, because the [Ca 2+ ] i threshold for cross-bridge interaction was presumably higher than the diastolic [Ca 2+ ] i in these hearts.

The risk-benefit relationship of open heart surgery in octogenarians is not well established. Eighty consecutive patients over the age of 80 who underwent cardiac operations under cardiopulmonary bypass were evaluated. Twenty-five patients were in functional class IV, 42 in class III, and 13 in class II. Forty-four patients had only coronary artery bypass grafts (CABG), 12 only aortic valve replacement (AVR), 6 only mitral valve replacement (MVR), 12 CABG and AVR, 4 CABG and MVR, 1 CABG and aneurysmectomy, and 1 had resection of left atrial myxoma. Operative mortality (within 30 days) was 12.5% for the group. Mortality was related to bleeding, left ventricular failure, primary ventricular fibrillation, pulmonary failure, and renal failure. Mortality was higher in patients with (1) advanced functional class, (2) mitral valve replacement, (3) postoperative hemorrhage, and (4) associated pulmonary disease. While a generally conservative approach is recommended for octogenarian patients, many with life-threatening cardiac disease, especially those free of major multisystem illnesses, should not be denied the benefit of surgical treatment.

This report examines the prevalence of hypertension, its management and control, and the use of antihypertensive medication, diet, and exercise in Chinese adults residing in the San Francisco community. Blood pressure (BP) was measured objectively using an automated oscillometric Dinamap recorder on 708 Chinese adults (295 men and 413 women; age range from 19 to 98 years, mean 59.7), and hypertension, defined as BP140/90 mm Hg and/or the use of antihypertensive medications, was found in 489 (69%), most of them immigrants from China. Although 202 patients (41%) received antihypertensive medications, only 28 (14%) achieved BP control (140/90 mm Hg), and in examining the self-management of hypertension, it was found that only 45% of patients used low-sodium diets, and 49% performed regular exercises foror = 30 minutesor = 3 times weekly.

We describe clinical and echocardiographic features in 19 patients with cardiac echinococcosis. Wide variability in the location and number of cysts inside cardiac cavities, septum, and pericardium is observed. The central role of two-dimensional echocardiography in making the diagnosis is stressed. This report has a significant clinical value in view of the large number of cases of a relatively rare condition.

From the Department of Medicine, The Johns Hopkins Hospital, Baltimore, Maryland. Dr. Mason is now in El Macero, California. Dr. Roberts is now with the Baylor Heart and Vascular Institute, Baylor University Medical Center, Dallas, Texas. Corresponding author: Dean T. Mason, MD, 44725 Country Club Drive, El Macero, California 95618. Nonpenetrating trauma to the chest often results in injury to the heart, which may vary in severity from immediately fatal cardiac rupture to asymptomatic cardiac bruises. Contusion of the myocardium, as evidenced by electrocardiographic abnormalities, has been the most common lesion found clinically, and rupture of the myocardium has been the most common injury found at autopsy following nonpenetrating chest trauma. The rupture usually involves the free wall of either or both ventricles and rapidly leads to death. On occasion, the ventricular septum is ruptured without perforation of a ventricular free wall. This report describes a patient who survived isolated rupture of the ventricular septum following blunt trauma to the chest and summarizes pertinent features of some cases that have been reported. • • • A 24-year-old laborer was in excellent health until October 1960, when he was involved in an automobile accident. He struck his chest against the steering wheel after hitting the rear of a truck and was knocked unconscious. Upon awakening approximately 1 hour later, he heard and felt a “purring” sensation over his precordium and was hospitalized. The patient had had no previous history of cardiac disease, and no precordial murmur

t n F fl a a t m n the beginning era of the diagnostic cardiac catheterization laboratory (in the early 1960s) at the ational Heart Institute in Bethesda, we performed any of our retrograde left heart catheterizations from he brachial artery via vessel cut-down. Because loss f the brachial pulse after the procedure was a probem in a few of these patients despite careful surgical echnique, it was postulated that peak reactive hypermic blood flow in the involved forearm, determined oninvasively before catheterization, might provide a eans for detecting the likelihood of this potential ifficulty. The reactive hyperemic response is the increase in lood flow immediately after restoration of the irculation after a short period during which arterial nflow is occluded. This is simply accomplished by he forearm arterial occlusion technique,1 with an uper arm–collecting cuff inflated to suprasystolic ressure and the use of a mercury-in-rubber strainauge plethysmograph placed at the mid-forearm to easure blood flow after release of the arterial occluion. Blood flow at rest is obtained, and then the eactive hyperemic response is determined in the forerm after restoring circulation to the ischemic limb fter 1, 2, 5, and 10 minutes of sequential arterial cclusion. Measurements of peak reactive hyperemic blood ow in the forearm were obtained in several patients mmediately before heart catheterization. Importantly, t became readily apparent that after restoration of the irculation after various periods during which arterial nflow was occluded, peak values of forearm blood ow after circulatory arrest were strikingly and sigificantly different (diminished) in patients with heart ailure compared with patients without heart failure Figure 1).2 On average, the peak level of reactive yperemia was attenuated by 2/3 of that relative to he those without heart failure. Furthermore, the magitude of the increase of the hyperemic response was ound to be a function of the duration of circulatory rrest in patients without heart failure, so that progresive increases in postischemic blood flow occurred s the duration of ischemia was prolonged; howver, this did not occur in patients with heart failure Figure 1).

Although the laser has been in existence for abut 30 years, its application in heart disease has only been examined in the past decade. Much attention has been given its exciting potential in treating coronary artery disease. Transmitted through a catheter comprised of one or more thin optical fibers which can be threaded nonsurgically into the coronary artery, the laser can ablate atherosclerotic plaque that obstructs the artery and diminishes blood flow to the myocardium. In clinical studies, the laser can treat some obstructive lesions that are not suitable for balloon angioplasty (i.e., long and diffuse lesions, very tight stenoses, ostial lesions, calcified lesions). In patients who failed balloon angioplasty due to severe dissection or abrupt closure, the laser may seal up the dissections and restore antegrade blood flow. In addition, the laser may have other applications and treatment modalities that are still under investigation. It may ablate ectopic ventricular foci, or terminate supraventricular tachyrhythmia by destroying the heart's abnormal conduction pathways. It can cut the hypertrophied septum that is associated with left ventricular outflow tract obstruction, or create a channel in the atrial septum as a palliative procedure in newborns with transposition of the great vessels. It may provide a wider orifice for blood flow within the heart in infants with pulmonary outflow obstruction and in adults with aortic valvular stenosis. It is also capable of fusing small thin-walled blood vessels together. Further, a more intriguing possibility is its use to bore several tiny channels in the myocardium to allow oxygenated blood from within the ventricular chamber to perfuse the ischemic heart tissue.

The United States has achieved over 97% immunization of children by school age and has reduced the incidence of vaccine-preventable diseases by more than 90% since the prevaccination era. However, children often do not receive immunizations at the recommended age, and in densely populated urban areas this delay in immunization has led to epidemics of measles. Correctable deficiencies of the immunization delivery system have been identified in these areas. To respond to needs, the public health infrastructure must be strengthened, and active participation from the private sector must be obtained, both in delivery of immunizations and in assessment of performance. Appropriate action must be stimulated by the provision of timely information on immunization coverage and on indicators of program performance at the local level. ( JAMA . 1992;267:1952-1955)

The possibility of increasing reduced blood flow in atherosclerotic coronary obstruction by catheter balloon dilatation offers a nonsurgical approach to relieve clinical coronary stenosis. To assess the ability of effectively dilating such diseased vessels by transluminal angioplasty, we used the Grüntzig balloon-tipped catheter in 12 fresh human cadaver hearts in which the intervention was performed in 21 noncalcified stenotic areas, including each of the three major coronary arteries. Quantitative coronary arteriography documented decreased obstruction of each lesion; luminal diameter increased 58% (1.9 +/- 0.2 mm to 2.8 +/- 0.3; p less than 0.001) and luminal diameter relative to the most proximal normal coronary segment diminished 61% (46 +/- 4% to 18 +/- 3%; p less than 0.001). Angioplasty was most successfully applied in proximal, discrete, noncalcified lesions of the right and left anterior descending coronaries; calcified, tortuous, middle and distal lesions and the left circumflex coronary were entered with difficulty or unapproachable. Histologic examination revealed microanatomic changes, most often endothelial disruption and atheroma compression, but no serious vascular tears. Dilatation beyond normal coronary diameter caused vessel rupture. This study extends elucidation of the value and limitations of percutaneous transluminal angioplasty in the clinical use of this technique in selected patients for relieving coronary obstruction without surgery.

Despite widespread use of treadmill stress in the detection of coronary disease, detailed information relating the important features of coronary pathoanatomy to the ischemic response noted on the electrocardiogram is lacking. Accordingly, 91 consecutive patients undergoing graded maximal exercise tests (MEXT) who were found to have clinical stenosis (larger than or equal to 75 per cent luminal narrowing) of at least one of the three major coronary arteries on coronary arteriography were evaluated. Positive MEXT was defined as larger than or equal to 0.1 mV horizontal or downsloping S-T segment depression larger than or equal to 0.08 second beyond J point. Over-all sensitivity of positive MEXT was 59 of 91 (65 per cent) patients; 11 of 26 (42 per cent) with single vessel stenosis, 20 of 30 (66 per cent) with two vessel disease and 28 of 35 (80 per cent) with three vessel disease. In patients with two vessel disease, the frequency (p less than 0.05) of positive MEXT was greater in those with (15 of 21;71 per cent) than in those without (five of nine; 55 per cent) stenosis of the left anterior descending artery. Concerning the site of intravessel stenosis, the frequency of positive MEXT was greater (p less than 0.05) with stenosis proximal to the left anterior descending artery in patients with one vessel disease. Quantification of total numbers of intra- and intervessel stenoses revealed 2.7 stenoses in the 59 patients with positive MEXT in contrast (p less than 0.01) to 1.9 in 32 patients with negative MEXT. Similarly, graded luminal narrowing index of severity of total stenoses per patient was 9.9 in those with positive MEXT compared (p less than 0.01) to 6.1 in those with negative MEXT. The poststenotic myocardial perfusion index, estimated by graded distal vessel opacification per major vessel disease, was only 1.5 in those with positive MEXT contrasted (p less than 0.01) to 2.4 in those with negative MEXT. These data indicate that sensitivity of positive MEXT in patients with coronary disease is most closely determined by the number of major coronary vessels involved, the total number of major vessels stenosed, the severity of total stenoses and poststenotic distal vessel perfusion. Less important factors are the precise site of intravessesl stenosis and the specific major coronary artery involved, although stenosis proximal to the left anterior descending artery favored positive MEXT. Unimportant variables were the quality of collateral vessels, ventricular function and prior inferior infarction. Angina occurred more frequently in those with positive MEXT, and marked degree of positive MEXT indicated stenosis proximal to the left anterior descending artery.

No data are available on determining right atrial and right ventricular size by two-dimensional echocardiography. We performed two-dimensional echocardiograms on eight human right-heart casts obtained at autopsy and on 50 patients who underwent complete left- and right-heart catheterization. Measurement of individual dimensions of the long and short axes of the right atrium and ventricle from right heart casts closely correlated with the volume of these structures as determined by water displacement. Further, individual dimensions by cross-sectional echo correlated well with actual casts dimensions. Subsequently, echocardiographic measurements of right atrial and ventricular long and short axes were obtained in the apical four-chambered view in a group of normals and compared with a group of patients with right ventricular volume overload states. Mean values for right atrial short-axis and long-axis measurements were greater in right ventricular volume overload patients than in normals: 6.5 +/- 0.3 vs 3.6 +/- 0.1 cm, and 6.0 +/- 0.3 vs 4.2 +/- 0.1 cm, respectively (both p less than 0.001). In addition, measurements of both individual dimensions as well as planed area of the right ventricle were greater in right ventricular volume overload patients than in normals: maximal short axis 6.1 +/- 0.3 vs 3.5 +/- 0.2 cm, mid-short axis 6.1 %/- 0.4 vs 2.8 +/- 0.2 cm, and area 40 +/- 2.6 vs 18 +/- 1.2 cm2 (all p less than 0.001). There were no differences in right ventricular long-axis measurement. Two-dimensional echocardiography provided better separation of normals from right ventricular volume overload patients than did M-mode techniques. Thus, two-dimensional echocardiography, with the apical four-chambered view, enables accurate visualization of the right atrium and ventricle in almost all patients. Futher, measurements of right atrial and right ventricular size by two-dimensional echocardiography readily distinguish normal patients from those with right ventricular volume overload.

Uncertainty exists regarding the determinants of mitral valve early diastolic closing velocity (E-F slope) in the echocardiogram. Accordingly, the mitral E-F slope, sequential atrioventricular flow in each third of diastole in the cineangiogram and an index of ventricular compliance (delta volume/delta pressure normalized by end-diastolic volume) were obtained in 10 normal subjects, 10 patients with coronary artery disease and marked dyssynergy and 9 patients with hypertrophic cardiomyopathy. The E-F slope of 103 +/- 20 mm/sec (mean +/- standard deviation) in normal subjects was greatly reduced in patients with coronary artery disease and hypertrophic cardiomyopathy (54 +/- 22 and 27 +/- 16 mm/sec, respectively, P less than 0.001). Transmitral flow of 52 +/- 25 cc during the initial third of diastole in normal subjects represented 48 +/- 10 percent of total flow and was diminished in patients with coronary artery disease and hypertrophic cardiomyopathy: 23 +/- 16 cc (25 +/- 24 percent) and 24 +/- 20 cc (20 +/- 11 percent), respectively (both P less than 0.001). The ventricular compliance index in normal subjects of 0.064 +/- 0.02 was also decreased identically in patients with coronary artery disease and hypertrophic cardiomyopathy: 0.029 (both P less than 0.001). The E-F slope was correlated with transmitral flow during the first third of diastole (r = 0.87) but was decreased to a slightly greater extent for any given reduction in flow in patients with hypertrophic cardiomyopathy than in patients with coronary artery disease. Although the E-F slope could not be related to compliance in individual patients, patients with an E-F slope of less than 75 mm/sec nearly always had diminished compliance. Thus, mitral E-F slope is primarily related to transmitral flow in the initial third of diastole. Reduced ventricular diastolic compliance usually results in diminished flow, and thus a decreased E-F slope, in patients with coronary artery disease or hypertrophic cardiomyopathy. The greater reduction in E-F slope for any decrement of flow in hypertrophic cardiomyopathy than in coronary disease may be due either to interference with vortex streaming or to alterations in the relation of the papillary muscles to the mitral valve induced by altered ventricular geometry; the finding indicates that factors in addition to flow may influence the E-F slope.