PubMed Health⌕ Search

Biomedical subjects

M Hodges

Publications and source records attributed to M Hodges.

At least 91 records · Page 5Linked to original sources

Flecainide versus quinidine: results of a multicenter trial.

In this multicenter trial, the efficacy and safety of flecainide, a new antiarrhythmic agent, were compared with those of quinidine, a standard antiarrhythmic agent in the United States. A randomized, parallel, placebo-controlled design was used. Flecainide was more effective than quinidine (p less than 0.0001) in reducing ventricular premature complexes, couplets and ventricular tachycardia. Flecainide continued to be effective in reducing ventricular arrhythmias during a 12-month follow-up period. The incidence of side effects was similar for the 2 drugs in both short- and long-term studies. Therefore, flecainide should be an excellent drug to use in treating patients with ventricular arrhythmias classified as either benign or potentially malignant.

Adult↗

A controlled trial of propafenone for treatment of frequent and repetitive ventricular premature complexes.

The effectiveness of oral propafenone was evaluated for the treatment of ventricular premature complexes (VPCs) in 12 patients, using a single-blind, dose-ranging trial followed by a double-blind comparison with placebo, and then an open-label, long-term protocol. During dose ranging, 8 of 12 patients achieved greater than or equal to 80% suppression of total VPCs (mean 83%) (p less than 0.01 vs single-blind placebo). Paired VPCs were suppressed greater than or equal to 90% and ventricular tachycardia was eliminated in 11 of the 12 patients (p less than 0.01). The effectiveness of propafenone for treatment of VPCs was confirmed during the double-blind trial (p less than 0.05 vs double-blind placebo) and during treatment for 6 months (p less than 0.05 vs initial single-blind placebo). Propafenone prolonged the PR interval by 16% (p less than 0.01 vs single-blind placebo) and the QRS interval by 18% (p less than 0.001). Left ventricular systolic performance decreased as assessed by 2-dimensional echocardiography (p less than 0.01 vs single-blind placebo). Propafenone increased serum digoxin levels in 5 of 5 patients (mean increase of 83%). Side effects included exacerbation of congestive heart failure (1 patient) and conduction abnormalities (2 patients). Thus, propafenone is effective for treatment of total and repetitive VPCs. Although generally well tolerated, the drug reduces left ventricular systolic function and atrioventricular conduction and increases serum digoxin levels.

Adult↗

Embolic potential of left ventricular thrombi detected by two-dimensional echocardiography.

We sought to determine whether an association existed between the echocardiographic appearance of left ventricular thrombi and systemic embolization. We reviewed the clinical and echocardiographic characteristics of 60 patients who underwent diagnostic two-dimensional echocardiography for left ventricular thrombi. Sixteen of these 60 patients (27%) had evidence of systemic embolization. Multiple echocardiographic characteristics of left ventricular thrombi were analyzed, including mobility, shape, heterogeneity, echo density, layering, central echo lucency, presence within an aneurysm, and association with low-density swirling echoes. Incidence of embolization was significantly higher in patients with thrombi that were mobile or protruded into the left ventricular cavity (p less than .002 and p less than .05, respectively). Bayesian analysis indicated that the pretest likelihood for embolization was 27% and increased in the presence of mobility, central echo lucency, and protrusion to 60%, 50%, and 40%, respectively. A stepwise regression indicated that mobility was the first and protrusion the second most helpful echocardiographic characteristic in identifying patients with embolic phenomena. Clinical features were of less help in identifying the risk for embolization of patients with left ventricular thrombi. Nine of 31 patients (29%) with recent myocardial infarction (less than 3 weeks) has emboli in contrast to five of 26 patients (19%) with remote myocardial infarction (greater than 3 weeks) (p = NS). The three patients without infarction had congestive cardiomyopathy and two had emboli.

Echocardiography↗

Left ventricular diastolic properties and filling characteristics during spontaneous angina pectoris at rest.

Diastolic left ventricular (LV) properties were studied at rest and during spontaneous angina pectoris during cardiac catheterization in 10 patients with severe coronary artery disease. During spontaneous angina there was a significant increase in LV filling pressures through diastole. The right ventricular end-diastolic pressure was measured at rest and during spontaneous angina in 7 of 10 patients and showed an increase from 7 +/- 3 to 10 +/- 4 mm Hg (mean +/- SD) (p less than 0.02). The T index (a measure of LV isovolumic relaxation) at rest was 51 +/- 17 ms and increased during angina to 58 +/- 12 ms (p less than 0.01), indicating an early diastolic relaxation dysfunction. Frame-by-frame LV volumes and corresponding pressures were analyzed from 3 consecutive beats in 5 of 10 patients. In 4 of these 5, the pressure-volume loop shifted upward and slightly to the right during angina. There was a significant increase in the rate of filling during mid-diastole with angina. Left atrial stroke work index increased by 35% during angina, suggesting an increased work load on the left atrium to maintain late diastolic filling.

Adult↗

Functional consequences of interventricular septal involvement in right ventricular infarction: echocardiographic, clinical, and hemodynamic observations.

Although ischemic involvement of the interventricular septum (IVS) may occur in patients with right ventricular infarction (RVI), the potential functional significance of such involvement has not been explored. In 10 patients with hemodynamically evident RVI, ischemic involvement of the IVS was assessed by measuring IVS systolic thickening on M-mode echocardiography. Six patients (group I) had decreased IVS systolic thickening, an echocardiographic indicator of ischemia, or infarction, while four (group II) did not. Group I had significantly higher right ventricular filling pressures (19 +/- 3 vs 12 +/- 5 mm Hg, p = 0.04) and right ventricular end-diastolic echocardiographic dimensions (32 +/- 8 vs 20 +/- 3 mm; p = 0.02) than group II. Paradoxic septal motion was noted only in group I patients (p = 0.01). Left ventricular filling pressures, left ventricular end-diastolic dimensions, and systolic thickening of the left ventricular posterior wall (LVPW) were not significantly different between the groups. Three group I patients died; all had decreased systolic thickening of both the IVS and LVPW. In each, autopsy confirmed infarction of the right ventricular free wall, IVS, and LVPW. In patients with right ventricular infarction, ischemic involvement of the interventricular septum may have important consequences for both right and left ventricular function.

Adult↗

State 1-State 2 Transitions in a Unicellular Green Algae : Analysis of In Vivo Chlorophyll Fluorescence Induction Curves in the Presence of 3-(3,4-Dichlorophenyl)-1, 1-dimethylurea (DCMU).

A study has been made on the State 1-State 2 transitions exhibited by the unicellular green algae Chlorella pyrenoidosa. Chlorophyll fluorescence induction curves from algae adapted to State 1 or State 2 have been analyzed and a comparison made with similar curves produced by decreasing the intensity of light going to the photosystem II reaction centers. In both cases, quenching of the maximum fluorescence yield (F(m)) and the initial fluorescence yield (F(o)) were observed so that the F(v)/F(m) ratio and the area above the induction curve (A(max)) remained constant. The State 1-State 2 transition also produced changes in the beta(max) component indicative of some alteration within photosystem II organization. The implications of these experiments on the in vivo mechanism for energy redistribution between the two photosystems are discussed in terms of changes in absorption cross-section rather than being due to spillover from photosystem II to photosystem I. These changes may reflect the phosphorylation of the light-harvesting chlorophyll a/b protein complex and its subsequent migration away from the photosystem II core leading to its closer association with photosystem I.

Journal Article↗

Comparison of flecainide with quinidine for suppression of chronic stable ventricular ectopic depolarizations. A double-blind randomized study in ambulatory outpatients.

In a randomized placebo-controlled double-blind trial, we compared flecainide to quinidine for treatment of ventricular ectopic depolarizations in 19 patients. The mean percent suppression of total ventricular ectopic depolarizations was 95% for flecainide and 56% for quinidine (p less than 0.05). A greater than 80% reduction of total ventricular ectopic depolarizations was obtained in eight of nine patients given flecainide and in five of ten patients given quinidine (p = 0.09). After the randomized protocol, the patients who had received quinidine were given flecainide; 9 of the 10 patients had greater than 80% reduction of total ventricular ectopic depolarizations. Flecainide produced 100% suppression of nonsustained ventricular tachycardia and 99.5% suppression of paired ventricular depolarizations. Flecainide prolonged the PR and QRS intervals; quinidine prolonged the PR and JTC intervals. Side effects were commoner with quinidine than flecainide (p = 0.06). Three other patients failed to complete the protocol because of serious adverse experiences.

Adult↗

Comparative hemodynamic effects of dopamine and dobutamine in patients with acute cardiogenic circulatory collapse.

The hemodynamic effects of dopamine (DPM) and dobutamine (DBM) were compared in 13 patients with acute cardiogenic circulatory collapse. All patients presented with acute pump failure and inadequate systemic perfusion, and most were hypotensive. Nine patients had an acute myocardial infarction (AMI); the other four patients had an acute decompensation of a previously stable ischemic cardiomyopathy, and presented with a low-output syndrome in the absence of documented AMI. Patients were studied with a randomized single crossover design using each patient as his own control. Both drugs were given at doses of 2.5, 5, and 10 micrograms/kg/min for periods of 10 minutes at each dose while hemodynamics were monitored. No other vasoactive drugs were used during the study. Because of advanced age or severe peripheral vascular disease, no patient was considered suitable for intra-aortic balloon counterpulsation. There were no significant differences between the two drugs with regard to heart rate, mean-arterial pressure, systemic vascular resistance, stroke work index, or mean right atrial pressure. DBM improved stroke index and cardiac index significantly (p less than 0.05) more than DPM at doses of 5 micrograms/kg/min. DPM increased left ventricular filling pressure (LVFP) more than DMB at 5 micrograms/kg/min (p less than 0.001) and at 10 micrograms/kg/min (p less than 0.05). Although both DPM and DBM are useful in acute cardiogenic circulatory collapse, there appear to be important differences in their effect on LVFP and in the mechanisms whereby they increase blood pressure.

Acute Disease↗

Suppression of ventricular ectopic depolarizations by flecainide acetate, a new antiarrhythmic agent.

Flecainide acetate, a new antiarrhythmic agent, was given orally to 11 hospitalized patients with chronic high-frequency ventricular ectopic depolarizations. Drug effectiveness was evaluated with a dose-ranging single-blind protocol, which included placebo control and washout periods. Twice-daily dosing (average daily dose 436 mg) completely suppressed all ventricular ectopic activity in five of 11 patients; average suppression in the 11 patients was 96.3%. Complex ventricular arrhythmias, which were present in all 11 patients during the placebo control period, were completely suppressed in eight patients and markedly suppressed in the other three patients during flecainide therapy. Ejection fraction and velocity of circumferential fiber shortening measured by M-mode echocardiography did not change significantly during flecainide dosing. Ventricular arrhythmias returned in all patients during the placebo washout period. During subsequent outpatient therapy with flecainide, significant suppression was present after 1 and 2 weeks of treatment (94.4% and 93.3%, respectively). Drug elimination was slow (average plasma half-life 20 hours). Ninety-five percent suppression of ventricular ectopic depolarization during dosing and 5% reappearance of arrhythmias during washout occurred with flecainide concentrations of 200-800 ng/ml. Side effects occurred in five of 11 patients, but did not require discontinuation of the drug. These results indicate that flecainide is a very effective antiarrhythmic agent that merits further clinical investigation.

Aged↗

Incidence of left-ventricular thrombosis after acute transmural myocardial infarction. Serial evaluation by two-dimensional echocardiography.

To study the incidence of left-ventricular thrombosis after transmural myocardial infarction, we performed serial two-dimensional echocardiography in 70 consecutive patients. Thirty-five patients had inferior-wall infarction: none had a left-ventricular thrombus. The other 35 had anterior-wall infarction: 12 had left-ventricular thrombi. Thrombi were diagnosed an average of five days after the infarction (range, one to 11 days). All patients with left-ventricular thrombi had severe apical-wall-motion abnormalities (akinesis or dyskinesis). Twenty-six of the 35 patients with anterior infarctions had apical akinesis or dyskinesis on echocardiography; left-ventricular thrombi developed in 12 of these 26 (46 per cent). We conclude that patients with severe apical-wall-motion abnormalities during acute transmural anterior myocardial infarction are at high risk for left-ventricular thrombosis. This high-risk group can be identified before the development of left-ventricular thrombi. Patients with inferior infarction or anterior infarction without a severe apical-wall-motion abnormality are at low risk.

Adult↗

Pirbuterol: a new oral sympathomimetic amine for the treatment of congestive heart failure.

Fourteen patients with refractory congestive heart failure (CHF) were given a single oral dose ranging from 5 to 30 mg of the new sympathomimetic drug pirbuterol. Hemodynamic measurements and plasma pirbuterol levels were obtained at control and then serially for 6 hours following drug administration. The optimal pirbuterol dose range was determined to be 20 to 30 mg. Ten patients received 20 to 30 mg pirbuterol. In this group cardiac index was significantly increased (1.9 to 2.6 L/min/m2, p less than 0.001). Pulmonary artery wedge pressures fell significantly (24 to 20 mm Hg, p less than 0.02). Decreases were also noted in mean pulmonary artery pressure (36 to 31 mm Hg, p less than 0.02), aortic diastolic pressure (71 to 65 mm Hg, p less than 0.05), systemic vascular resistance (1782 to 1201 dynes. sec. cm-5, p less than 0.001), and pulmonary vascular resistance (265 to 175 dynes.sec.cm-5, less than 0.001). Systolic and mean aortic pressure and heart rate showed no significant change from control. Hemodynamic effects persisted for 5 hours. Pirbuterol was clinically well tolerated. The mechanism of action is unclear at this time, but both inotropic and vasodilator effects are possible. Pirbuterol orally has a marked and prolonged salutary hemodynamic effect and offers promise in CHF treatment.

Administration, Oral↗

Observations on detecting left ventricular thrombus with two dimensional echocardiography: emphasis on avoidance of false positive diagnoses.

Observations made in detecting left ventricular thrombus with two dimensional echocardiography in 25 patients are reviewed. In 20 patients thrombus was documented on angiography, surgery postmortem examination or serial two dimensional echocardiographic findings; in the remaining five patients two dimensional echocardiographic findings of thrombus were unequivocal. In all 25 patients wall motion abnormalities ranging from hypokinesia to frank dyskinesia were present at the site of the thrombus. Twenty-three patients had an apical thrombus; two had thrombus adjacent to the inferior wall. Clear delineation of the endocardium and thrombus margin was considered essential to the correct diagnosis of thrombus. Both intracavitary motion of the thrombus margin and a layering effect were noted infrequently although they were of benefit in identifying an intracardiac mass as thrombus. In addition, serial evaluations were helpful in establishing the correct diagnosis. False positive diagnoses can be minimized if one understands certain technical limitations of this method and correctly identifies apical structures that are not thrombi. Axial and lateral resolution problems inherent with this technique can produce intracavitary echoes that may simulate thrombi. In addition, normal or pathologic structures at the apex may also simulate thrombi. These structures include the papillary muscles, muscular trabeculae, chordal structures and tangential information from normal myocardium. Varying the sector orientation or acoustic window, or both, will aid in correctly identifying these structures and distinguishing them from left ventricular thrombi.

Blood Coagulation↗

Combined left ventricular aneurysmectomy, mitral valve replacement and aortocoronary bypass grafting: results of surgery.

Eighteen patients with ischemic heart disease who underwent left ventricular aneurysmectomy (LVA) and concomitant mitral valve replacement (MVR) for severe mitral regurgitation during 1973-1978 were identified. Eleven patients (61%) underwent aortocoronary bypass procedures (CABG) at the same operation. All patients had New York Heart Association class III or IV symptoms of congestive heart failure; six (33%) had disabling angina pectoris and four (22%) had had life-threatening ventricular tachycardia. Surgical mortality was 11%. The survival rate at 2 and 3 years was 80% and 57%, respectivey, with a mean follow-up of 21 months (range 4-56 months). At follow-up all patients had improved symptomatically by at least one functional clas; four patients were class II and six were class 1. The mean values (+/ SEM) for preoperative cardiac index, left ventricular end-diastolic pressure and ejection fraciton were 2.0 +/- 0.1 l/min/m2, 22 +/- 2.3 mm Hg, and 30 +/- 3.5%, respectively. Postoperative right-heart catheterization in seven patients revealed no difference between preoperative and postoperative resting cardiac index and pulmonary wedge pressure, although all seven patients claimed significant improvement. Thus, although resting hemodynamics may not be altered, combined LVA, MVR and CABG can be performed with acceptable surgical risk in these seriously ill patients and can provide excellent symptomatic improvement with good long-term survival.

Aged↗