Left ventricular function in ischaemic heart disease. A review

The clinical significance of the abnormalities seen at left ventriculography in ischaemic heart disease is discussed. Aneurysms may be recognized when left ventriculography is combined with coronary arteriography to show the characteristic obliteration of the supplying artery. Localized areas of abnormal contraction seen at rest are almost certainly indicative of infarcts. Similar areas provoked by exercise or atrial pacing represent the site of acute ischaemia. The ischaemic ventricle may be recognized by abnormal response to exercise, even in the absence of angina. The abnormal response may be reversed by successful revascularization surgery.

Hemodynamic factors associated with the production of pain in angina pectoris

18 patients with uncomplicated angina pectoris were studied to ascertain the relative significance of individual hemodynamic factors in the production of angina pectoris. Each hemodynamic determinant of myocardial oxygen consumption (heart rate, systemic arterial pressure, LVEDP, and LV dp/dt max) were either altered or controlled as discretely as possible with the use of right atrial pacing, propranolol, phentolamine and ouabain, and the effects of these changes were observed on the onset and total duration of pain. Only heart rate correlated closely with the precipitation of angina. The systemic arterial pressure, LVEDP and LV dp/dt max did not correlate with the production and abolition of angina pectoris. The results indicate that drugs acting only against the effect of sympathetic stimulation of the sinus node would be a major advantage in the treatment of patients with angina pectoris. The unexpected finding that phentolamine did not ameliorate pain in patients with angina pectoris casts doubts as to whether nitroglycerine relieves anginal pain by lowering the systemic arterial pressure.

In vitro immunization against human tumor cells with tumor cell fractions

Tumor cell fractions isolated from tumor lines SH-3 (breast carcinoma) and RPMI-7932 (malignant melanoma) by differential centrifugations were capable of transforming lymphocytes into cytotoxic effector cells. Lymphocytes cultured alone in human AB plasma did not become cytotoxic to tumor cells. However, when cultured with tumor cell fractions sedimented at 1000 X g(R1), 20,000 X g(R2), and 100,000 X g(R3), these lymphocytes became markedly cytotoxic to specific tumor targets in a 3.5-hr (51)Cr release assay. R2 fractions were significantly more immunogenic than were R3 fractions (p less than 0.05). Although lymphocytes sensitized with SH-3 tumor cell fractions were cytotoxic to SH-3 tumor cells, they were also cytotoxic to cells from RPMI-7932 and RPMI-8322 (malignant melanoma) tumor lines and vice versa. Cells from tumor lines HT-29 (colon carcinoma) and COLO 110 (ovary carcinoma) were significantly less susceptible to lysis by effector cells generated against SH-3. These immune cells, although capable of killing cells from tumor lines, were not able to lyse cells from autochthonous normal lymphoid lines or normal lymphocytes that have been transformed by phytohemagglutinin. Tumor cell fractions were not immunogenic at low (5- to 20-mul/0.75 ml) concentrations; an increase of 4- to 10- fold in their concentrations was usually followed by a decrease in immunization.

The investigation of a recurrence of an AHC virus epidemic at Lucknow: a serosurvey for AHC virus antibodies before and after the epidemic

An epidemic of acute haemorrhagic conjunctivitis (AHC) recurred at Lucknow during July to September 1975, after a gap of 4 years. Out of the 35 cases investigated thoroughly, 20 Entero-70-like cytopathogenic agents were isolated from the conjunctiva which were neutralized by antisera against AHC virus J670/71 of Japan. Seroconversion was seen in 7 out of 11 paired sera from patients. Serological study was also done on 100 sera collected before the AHC epidemic of 1971, 100 sera after 1971 and 100 sera after 1975 epidemic. There were no neutralizing antibodies in the pre-epidemic period, while 18% of sera after the first epidemic and 32% after the second epidemic showed antibodies. The incidence of antibodies was highest (43%) in children aged below 10 years. Of the children born after the first epidemic, 44% had antibodies. Thus our findings show that the AHC virus appeared for the firt time at Lucknow in 1971 and the almost complete absence of disease in children, and its mildness during second epidemic, may be due to immunity.

Left ventricular angiography on exercise. A new method of assessing left ventricular function in ischaemic heart disease

Left ventricular function was studied in 17 patients with ischaemic heart disease and compared with 4 patients with normal left ventricular function. The patients in the homogeneous group of ischaemic heart disease were further subdivided into those 'without angina' (n=5) and those 'with angina' (n=12), depending upon the presence of angina during supine leg exercise at the time of definitive study. At rest there was no significant difference in the heart rate, cardiac output, stroke volume, and left ventricular end-diastolic pressure (LVEDP) in the three groups. During exercise the cardiac output and stroke volume were significantly depressed and LVEDP was significantly raised in the ischaemic heart disease group as a whole but within this group failed to show any significant difference in patients with and without angina. The left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV) measurements showed clear separation of these three groups only on exercise. On exercise, there was decrease in LVEDV and LVESV (P less than 0.05; P less than 0.02) in the group with normal left ventricular function, no change in the group with ischaemic heart disease without angina, and striking increase in LVEDV and LVESV in the group with ischaemic heart disease and angina (P less than 0.01 and P less than 0.02, respectively). This angiographic method of assessing left ventricular function shows clear separation of the three groups and also highlights the significance of angina. Ejection fraction (EF), a commonly measured parameter of left ventricular function, failed to reflect consistent changes on exercise as compared to values at rest which emphasizes the limitations of the measurement of ejection fraction at rest.

Lymphocyte transformation induced by human granulocytes

Contrary to previous reports, human granulocytes are capable of causing transformation of allogeneic lymphocytes. Pretreatment of granulocytes with mitomycin C results in nonstimulation, but untreated granulocytes are capable of stimulating lymphocytes. Nonstimulation with mitomycin C-treated granulocytes may result from the reduced viability of the cells. It is concluded that granulocytes possess alloantigens that stimulate lymphocytes in vitro.

Localization of left ventricular ischaemia in angina pectoris by cineangiography during exercise

Cineangiography of the left ventricle during exercise has been used in an attempt to define the area of ischaemic myocardium in patients suffering from angina pectoris in whom coronary artery surgery was contemplated. A correlation was established between the site of coronary artery obstruction and the area of abnormal myocardial contraction. This method of localization of regional left ventricular ischaemia may furnish useful diagnostic information when coronary reconstructive surgery is contemplated in patients with exercise-induced angina pectoris.

Effect of water-soluble adjuvants on in vitro lymphocyte immunization

Water-soluble adjuvants prepared from Mycobacteriim smegmatis and human mixed mycobacteria strains C, DT, and PN were found to increase lymphocyte response in one-way mixed-lymphocyte culture and in vitro immunization to cultured human tumor cells. Phytohemagglutinin-induced lymphocyte blastogenesis, however, was depressed by water-soluable adjuvants.