Jeffrey Fisher

Relation of concentric left ventricular hypertrophy and extracardiac target organ damage to supranormal left ventricular performance in established essential hypertension

Increased cardiac performance has been documented in patients with early systemic hypertension, but its prevalence and determinants in patients with uncomplicated sustained essential hypertension have not been characterized. Radionuclide cineangiography in 116 patients with uncomplicated essential hypertension showed that 12 of 116 (10%) had supranormal resting left ventricular (LV) ejection fraction (greater than 70%, above the highest value in normal subjects), while 104 patients had a normal resting ejection fraction (45 to 70%). Patients with a high resting ejection fraction had higher systolic and diastolic blood pressure compared with patients with normal resting ejection fraction (182 mm Hg vs 169, p less than 0.01, and 110 vs 103, p less than 0.05, respectively), markedly greater echocardiographic LV mass (136 vs 94 g/m2, p less than 0.01), smaller ventricular dimensions in systole (2.5 vs 3.1, p less than 0.01) and diastole (4.4 vs 4.9, p less than 0.05), and higher relative wall thickness (0.61 +/- 0.20 vs 0.39 +/- 0.98, p less than 0.001). Patients with supranormal resting ventricular performance had lower end-systolic wall stress than normal volunteers or patients with normal resting LV function (48 vs 64 vs 74 X 10(3) dynes/cm2, respectively). Patients with an elevated LV ejection fraction also had significantly more abnormal funduscopic examinations and greater proteinuria. Thus, a subset of essential hypertensive patients with moderately to severely elevated blood pressure developed marked concentric LV hypertrophy associated with subnormal end-systolic stress and supranormal LV performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Function of the hypertrophied left ventricle at rest and during exercise: Hypertension and aortic stenosis

Assessment of left ventricular function may be of value in patients with pressure-loaded, hypertrophied left ventricles for the purpose of characterizing such patients as to prognostic risk. To determine whether left ventricular function is in part independent of loading stresses in such patients, and to assess the effects of removal of loading factors, we have reviewed preliminary data in 60 patients with essential hypertension and in 26 patients with aortic stenosis who were studied with radionuclide cineangiography. Patients with hypertension manifested a poor but statistically significant direct relationship between systolic arterial pressure and left ventricular ejection fraction at rest, and a poor but significant inverse relationship between systolic pressure and the magnitude of change in ejection fraction from rest to exercise. However, a strong correlation existed between echocardiographic systolic fractional shortening and end-systolic wall stress at rest. Nonetheless, many patients with normal fractional shortening-end-systolic wall stress relationships had subnormal ejection fraction responses during exercise; the two patients with subnormal fractional shortening-end-systolic wall stress relationships at rest also had subnormal fractional shortening-end-systolic wall stress relationships during exercise. Arterial pressure alone was not predictive of these functional responses. These data suggest that hypertensive patients can be categorized on the basis of left ventricular function at rest and during exercise, independent of arterial pressure. Among patients with aortic stenosis, ejection fraction at rest averaged 67 percent before valve replacement (normal = 57 percent, p less than 0.01), and changed little after operation (71 percent, not significant). However, potential functional benefits of afterload reduction in the patient with the chronically pressure-loaded, hypertrophied left ventricle was suggested by results during exercise: before surgery the ejection fraction during exercise averaged 56 percent (normal = 71 percent, p less than 0.01), but after valve replacement it rose to 72 percent (not significant versus normal). Thus, our data in patients with aortic stenosis supplement our data in patients with hypertension, indicating that myocardial functional improvement can be achieved by unloading therapy in patients with long-standing left ventricular pressure-loading and hypertrophy.

Digital subtraction intravenous left ventricular angiography: Comparison with conventional intraventricular angiography

Standard contrast left ventriculography with catheter placement into the left ventricle entails risks and inconvenience. Computer-based digital subtraction techniques now permit high contrast left ventriculography after intravenous administration of contrast medium. To compare the accuracy of intravenous digital subtraction left ventriculography with film-based, standard contrast ventriculography, we assessed left ventricular function by both methods in 32 patients (8 with valvular disease, 22 with coronary disease and 2 with atypical pain). Studies in 31 of 32 patients were considered. Left ventricular ejection fraction by standard contrast ventriculography ranged from 24 to 88%. Digital subtraction angiography was performed with bolus injection of radiopaque contrast material (30 cc at 20 cc/s) into the inferior vena cava. The two methods correlated closely in end-diastolic volume (correlation coefficient [r] = 0.96, probability [p] less than 0.001), end-systolic volume (r = 0.97, p less than 0.001) and ejection fraction (r = 0.98, p less than 0.001). Segmental function was assessed visually; precise agreement existed between the two techniques in 123 (79%) of the 155 segments (p less than 0.001). It is concluded that intravenous digital angiography provides left ventricular images of sufficiently good quality to allow accurate quantitative assessment of global left ventricular function and volumes as well as determination of regional function.

Exercise left ventriculography utilizing intravenous digital angiography.

Exercise left ventriculography has been shown to be a sensitive and specific tool for the detection of coronary artery disease. At the present time, such studies require radionuclide-base methods. Computer-based techniques recently have been shown to provide high resolution images of the left ventricle when the levophase of an intravenous injection of radiopaque contrast medium is imaged with fluoroscopy. To evaluate the possible efficacy of using intravenous digital subtraction left ventriculograms in exercise ventriculography, such ventriculograms were performed at rest and during maximal supine bicycle exercise in 31 patients. Studies that could be analyzed were obtained in 29 patients. In 21 patients with coronary artery disease, ejection fraction was 58% at rest and 45% with exercise (p less than 0.001 vs. rest). In contrast, in seven patients with no coronary artery disease, ejection fraction was 65% at rest and 69% with exercise (difference not significant). In a subgroup of 8 patients with severe coronary obstruction, the change in ejection fraction from rest to exercise was -18%, while in the remaining 13 patients with less severe disease, it was -9% (p less than 0.001). All patients with coronary artery disease manifested new or worsening segmental wall abnormality with exercise, compared with two of seven patients without coronary disease (p less than 0.01). Sixteen patients underwent rest and exercise radionuclide cineangiography in addition to digital subtraction angiography. There was a strong correlation between the two techniques for ejection fraction at rest (r = 0.78, p less than 0.001), ejection fraction and with exercise (r = 0.83, p less than 0.001) and change in ejection fraction from rest to exercise (r = 0.88, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic effects of nifedipine versus hydralazine in primary pulmonary hypertension

The acute hemodynamic effects of both sublingual nifedipine (N) and intravenous hydralazine (Hy) were studied in 5 patients with primary pulmonary hypertension to ascertain whether the capacity for pulmonary vasodilatation was generalized or drug-specific, and to determine which of the 2 agents had preferential pulmonary vasodilatory effects. For the group as a whole, neither N nor Hy produced changes in heart rate, mean pulmonary capillary wedge or right atrial pressures. Both N and Hy reduced mean systemic arterial pressure (before N 90 +/- 8 mm Hg, after N 76 +/- 7 mm Hg, p less than 0.01; before Hy 92 +/- 11 mm Hg, after Hy 68 +/- 8 mm Hg, p less than 0.05), and decreased systemic vascular resistance (before N 1,558 +/- 645 dynes s cm-5, after N 1,192 +/- 430 dynes s cm-5, p less than 0.05; before Hy 1,700 +/- 415 dynes s cm-5, after Hy 957 +/- 285 dynes s cm-5, p less than 0.05). In addition, N administration resulted in an increased cardiac output (before N 4.5 +/- 2.0 liters/min, after N 4.8 +/- 2.0 liters/min, p less than 0.01); Hy administration was associated with a more varied effect on cardiac output (before Hy 4.0 +/- 1.0 liters/min, after Hy 5.3 +/- 1.8 liters/min, p less than 0.10, difference not significant [NS]).(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural anaesthesia for labour and Caesarean section in a parturient with a single ventricle and transposition of the great arteries

We describe a case of a 29-year-old parturient with a single ventricle and transposition of the great arteries who had lumbar epidural analgesia/anaesthesia with a local anaesthetic for labour, emergency Caesarean section and postoperative pain. Her outcome and that of her baby was successful. The anaesthetic techniques used in other parturients with similar congenital cardiac anomalies are reviewed.RésuméOn décrit le cas d’une parturiente de 29 ans avec un ventricule unique et une transposition des gros vaisseaux qui a subi une anesthésie-analgésie épidurale lombaire avec un anesthesique local lors du travail, la césarienne d’urgence et l’analgésie postopératoire. L’issue chez la mere et le bébé se deroula sans complication. Les techniques anesthésiques utilisées chez d’autres parturientes avec des anomalies cardiaques congénitales similaires sont revues.

Hemodynamic assessment of intravenous bepridil administration in ischemic heart disease.

The hemodynamic effects of intravenous administration of bepridil were evaluated in 17 patients with chronic coronary artery disease who underwent cardiac catheterization. Of the 17 patients, 8 received bepridil, 2 mg/kg of body weight, for 15 minutes followed by 1 mg/kg for 15 minutes (group A), and 9 received 3 mg/kg followed by 1 mg/kg (group B). In group A, the systemic blood pressure (BP) decreased (p less than 0.05) and left ventricular end-diastolic pressure increased minimally (p less than 0.05). Heart rate (HR), pulmonary artery pressure, cardiac output (CO), stroke index, pulmonary vascular resistance and systemic vascular resistance (SVR), stroke work index, contractility (+dP/dt) and double product (HR X systolic BP) showed no significant change after bepridil infusion. In contrast, in group B, while +dP/dt decreased (p less than 0.01), SVR also showed a strong downward trend and changed significantly more than in group A; in the context of the latter alteration, CO increased significantly. In addition, the double product (less than 0.025) and systemic BP (p less than 0.05) decreased, though other parameters did not vary significantly. Thus, although a modest dose-related negative inotropic effect (decreased +dP/dt) was seen, dose-related direct systemic vasodilatation (decreased SVR) led to improved cardiac performance (increase in cardiac index) at the larger dose.

Nifedipine in Pulmonary Arterial Hypertension: Importance of Raynaud's Phenomenon

We studied (via acute vasodilator testing with nifedipine) 27 patients with pulmonary arterial hypertension (PAH) (11 primary, 16 secondary PAH, [including six patients with Raynauds phenomenon]) in order to identify predictors of hemodynamic response and specifically to assess whether patients with Raynauds phenomenon and pulmonary hypertension were more likely to respond to nifedipine. Nifedipine decreased resting mean pulmonary artery (PA) pressure and pulmonary vascular resistance (PVR) in patients with Raynauds phenomenon (delta PA - 6.8 +/- 10.5 mm Hg; delta PAD - PCW gradient - 9.3 +/- 4.7 mm Hg; delta PVR - 255 +/- 201 dynes.s.cm-5, all p less than .05) versus (delta PA 0.3 +/- 4.0 mm Hg; delta PAD - PCW gradient 0.4 +/- 5.0 mm Hg; delta PVR - 58 +/- 132 dynes.sec.cm-5, all NS), in the patients without Raynaud syndrome. These data suggest that patients with both primary and secondary PAH may benefit from nifedipine therapy, but that patients with Raynauds phenomenon may respond particularly well, perhaps because of vasodilator-reversible pulmonary vasoconstriction. An alternative hypothesis is that prior chronic vasodilator therapy in the majority of our patients with Raynauds phenomenon preserved pulmonary vasoreactivity.

Prognostication in patients with coronary artery disease: preliminary results of radionuclide cineangiographic studies.

Radionuclide cineangiography during exercise has frequently been demonstrated to be of value in the diagnosis of coronary artery disease (Borer et al. 1977, 1979, 1980). However, the quantitative nature of the technique lends itself readily not only to the detection of disease, but also - by permitting determination of the extent of change in left ventricular ejection fraction from rest to maximal exercise — to assessment of the functional severity of ischemia in a given individual (Borer et al. 1977, 1978, 1979, 1980; Kent et al. 1978). It seems intuitively reasonable that prognosis of the individual patient should depend directly on the functional severity of ischemia from which he or she suffers. Parenthetically, it is increasingly clear that coronary arteriography, as it is currently performed and analyzed, provides only a general guide to the severity of ischemia (Borer et al. 1979).

Hemodynamic Changes during Retrograde Left-Heart Catheterization in Patients with Aortic Stenosis

Pulmonary artery pressures in patients with aortic stenosis have been related to postoperative prognosis and surgical risk. However, while right- and left-heart pressures should be measured simultaneously, a catheter lying across the stenotic aortic valve might alter left- and right-heart pressures. To assess this phenomenon, right- and left-heart pressures were recorded before and after retrograde crossing of the aortic valve in 51 patients (30 patients with and 21 without aortic stenosis). In aortic stenosis, the mean pulmonary artery pressure increased (p less than 0.001) after transaortic valvular pressure catheter placement (average 4 mm Hg, peak 19 mm Hg); in the absence of aortic stenosis, the mean pulmonary artery pressure did not change (average 0 mm Hg; NS). A similar response was noted for the mean pulmonary capillary wedge pressure. Hemodynamic changes did not correlate with the severity of aortic stenosis or with left ventricular performance. Right-heart pressures should be determined without transaortic valvular catheter in place, if accurate interpretation of the hemodynamic effects of aortic stenosis is to be achieved.