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H Hultgren

Publications and source records attributed to H Hultgren.

18 recordsLinked to original sources
PubMed1991

Ten-year incidence of myocardial infarction and prognosis after infarction. Department of Veterans Affairs Cooperative Study of Coronary Artery Bypass Surgery.

BACKGROUND: The 10-year incidence of myocardial infarction (fatal and nonfatal) and the prognosis after infarction were evaluated in 686 patients with stable angina who were randomly assigned to medical or surgical treatment in the Veterans Administration Cooperative Study of Coronary Artery Bypass Surgery. METHODS AND RESULTS: Myocardial infarction was defined by either new Q wave findings or clinical symptoms compatible with myocardial infarction accompanied by serum enzyme elevations with or without electrocardiographic findings. Treatment comparisons were made according to original treatment assignment; 35% of the medical cohort had bypass surgery during the 10-year follow-up period. The overall cumulative infarction rate was somewhat higher in patients assigned to surgery (36%) than in medical patients (31%) (p = 0.13) due to perioperative infarctions (13%) and an accelerated infarction rate after the fifth year of follow-up (average, 2.4%/yr in the surgical group versus 1.4%/yr in the medical group). The 10-year cumulative incidence of death or myocardial infarction was also higher in surgical (54%) than in medical (49%) patients (p = 0.20). According to the Cox model, the estimated risk of death after infarction was 59% lower in surgical than in medical patients (p less than 0.0001). The reduction in postinfarction mortality with surgery was most striking in the first month after the event: 99% in the first month (p less than 0.0001) and 49% subsequently (p less than 0.0001). The estimated risk of death in the absence of infarction was nearly identical regardless of treatment (p = 0.75). Exclusion of perioperative infarctions did not alter the findings. CONCLUSIONS: Although surgery does not reduce the incidence of myocardial infarction overall, it does reduce the risk of mortality after infarction, particularly in the first 30 days after the event (fatal infarctions).

Angina Pectoris↗
PubMed1990

The electrocardiogram at rest and exercise during a simulated ascent of Mt. Everest (Operation Everest II).

To evaluate the effect of extreme altitude on cardiac function in normal young men, electrocardiograms were recorded at rest and during maximal exercise at several simulated altitudes up to the equivalent of the summit of Mt. Everest (240 torr or 8,848 m). The subjects spent 40 days in a hypobaric chamber as the pressure was gradually reduced to simulate an ascent. Changes in the resting electrocardiogram were evident at 483 torr (3,660 m) and were more marked at 282 torr (7,620 m) and 240 torr (8,848 m). They consisted of an increase in resting heart rate from 63 +/- 5 to a maximum of 89 +/- 8 beats/min; increase in P-wave amplitude in inferior leads; right-axis shift in the frontal plane; increased S/R ratio in the left precordial leads; and increased T negativity in V1 and V2. No significant arrhythmias or conduction defects were observed. Most changes reverted to normal within 12 hours of return to sea level, with the exception of the frontal-plane axis and T-wave alterations. Maximal cycle ergometer exercise at 282 torr (7,620 m) and 240 torr (8,848 m) resulted in a heart rate of 138 +/- 7 and 119 +/- 6 beats/min at the 2 altitudes, respectively. No ST depression or T-wave changes suggestive of ischemia occurred despite a mean arterial oxygen saturation of 49% and a mean pH of 8 during peak exercise. Occasional ventricular premature beats were observed during exercise in 2 subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

The sleep electrocardiogram at extreme altitudes (Operation Everest II)

To evaluate the effect of sleep at extreme altitudes upon heart rate and rhythm, continuous sleep monitoring was performed in 8 normal young men during a 40-day simulated ascent of Mt. Everest in a hypobaric chamber. Recordings were made for 1 hour before sleep, during sleep and for 1 hour after awakening in all subjects at 760 torr (sea level), in 7 subjects at 390 torr (5,490 m), in 6 at 347 torr (6,100 m) and in 4 at 282 torr (7,620 m). The following results were obtained: periods of sinus bradycardia occurred during sleep in all subjects at 3 altitudes with a mean heart rate of 41 +/- 0.5 beats/min compared to a rate of 44 +/- 2 beats/min at sea level; cycling of the heart rate, presumably due to periodic breathing, occurred in 14 of 17 studies at altitude but not at sea level (cycles consisted of bradycardia [40 beats/min] for 13 seconds and tachycardia [120 beats/min for 5 seconds]; and arrhythmias were observed in all subjects during sleep and consisted of transient bradycardia (heart rates as low as 20 beats/min), sinus pauses frequently associated with escape rhythms and occasional blocked P waves. No arrhythmias were observed at sea level. Simultaneous records of respiration and the electrocardiogram at 12,500 feet (3,810 m) in 5 other normal subjects revealed tachycardia occurring during hyperpnea and bradycardia occurring during apnea. Data indicate that during sleep in normal young subjects at high altitude, cycling of the heart rate with periodic breathing is common, as are bradyarrhythmias. The mechanism of these arrhythmias has yet to be defined.

Adult↗
PubMed1987

Ten-year effect of medical and surgical therapy on quality of life: Veterans Administration Cooperative Study of Coronary Artery Surgery.

The long-term effect of medical vs surgical therapy on quality of life was evaluated by New York Heart Association functional classification, severity of angina and exercise performance in 427 surviving patients with stable angina at 10 years. Surgically assigned patients had significantly more improvement in functional classification, relief of angina and exercise performance at 1 and 5 years than medically assigned patients. Relative to entry, functional classification was improved in 65% of surgically treated patients at 1 year and in 51% at 5 years, compared with 45% and 40%, respectively, of medically treated patients. Marked improvement in angina was observed in 49% of surgical patients at 1 year and in 41% at 5 years, vs 12% and 17%, respectively, in medical patients. At 10 years, quality of life was not significantly different in the 2 treatment groups: 52% of surgical patients had an improved functional classification, compared with 46% of medical patients, while 33% of surgical and 37% of medical patients had a marked improvement in angina. Exclusion of medical and surgical nonadherers had little effect on the 1- and 5-year comparisons. The 10-year treatment differences, however, were accentuated when 123 medically assigned patients who later underwent operation and who benefited from it were excluded from the analysis. In surgical patients, a strong association was observed between graft patency and functional class at 1 year, but not at 5 and 10 years. In general, patients with some or all grafts open had more improvement in functional classification than patients with all grafts closed.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1985

Angina scoring method in the Veterans Administration randomized study of bypass surgery.

An angina scoring method was designed in the Veterans Administration Coronary Artery Bypass Surgery Study in 1973 to evaluate the effect of medical versus surgical therapy on relief of angina. The score measures the frequency of angina, type of activity producing angina, and use of medications. The score is based on objective responses to specific questions, is easy to compute, and is designed to be administered by a physician familiar with symptoms of angina and coronary artery disease. In this report, the authors evaluate the reproducibility, validity, and utility of the angina score in Veterans Administration study patients. Extensions of the scoring method to include newer cardiac drugs and comparison with other methods of grading the severity of angina are also discussed.

Angina Pectoris↗
PubMed1985

Long-term mortality and morbidity results of the Veterans Administration randomized trial of coronary artery bypass surgery.

The long-term effect of coronary artery bypass grafting on mortality and the incidence of nonfatal myocardial infarction was evaluated in 686 patients in the randomized Veterans Administration study of medical vs surgical treatment for stable angina. Average follow-up was 11.2 years. The 11 year cumulative mortality rates for all patients and for the 595 patients without left main diseases were not significantly different in the two treatment groups. The 7 year mortality rates were 30% in medically assigned and 23% in surgically assigned patients (p = .043) and the 11 year rates were 43% and 42% (p = .45), respectively. The rates in patients without left main disease were 28% for medical and 23% for surgical treatment policy at 7 years (p = .267) and rose to 42% in both groups at 11 years (p = .813). A statistically significant reduction in mortality with surgical policy was found both at 7 and 11 years in high-risk patients without left main disease who had multiple clinical or angiographic risk factors or both. In the subgroup with angiographic high risk, the 7 year mortality rates were 48% in medically assigned and 24% in surgically assigned patients (p = .002); the 11 year rates were 62% and 50%, respectively (p = .026). Corresponding rates in the clinically defined high-risk group were 48% vs 28% (p = .003) at 7 years and 64% vs 51% (p = .015) at 11 years for medical vs surgical policy, respectively. For the subgroup of patients with combined angiographic and clinical high risk, the 7 year mortality rates were 64% for medical and 24% for surgical policy (p = .002); the 11 year rates were 76% and 46%, respectively (p = .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1981

Effect of bypass surgery on survival in patients in low- and high-risk subgroups delineated by the use of simple clinical variables.

A multivariate risk function was developed on data from all 508 medical patients in the Veterans Administration (VA) randomized study of coronary bypass surgery. The variables, in order of importance, were ST-segment depression on resting ECG, history of myocardial infarction, history of hypertension and New York Heart Association functional classification III or IV. These noninvasive variables have been reported to be risk factors in natural-history studies of coronary heart disease (CHD). Applying the risk function to medical and surgical patients of the 1972-1974 cohort yielded a 5-year probability of dying for each patient. Investigation of treatment effects in approximate terciles obtained by collapsing the probability distribution into low-, middle- and high-risk groups showed that surgery was beneficial for patients in the high-risk tercile even after removal of patients with left main coronary artery disease (17% surgical vs 34% medical mortality at 5 years; p less than 0.01). This finding was accentuated when patients in the 10 hospitals with the lowest operative mortality (3.3%) were compared. Mortality results in the low-risk tercile favored medical treatment (medical vs surgical mortality 7% vs 17%; p less than 0.05). The risk function predicted mortality well not only for te VA medical group, but also for an independent symptomatic CHD population from the University of Alabama arteriography registry. This report further delineates the advantages and limitations of coronary bypass surgery in CHD patients with chronic stable angina.

Coronary Artery Bypass↗
PubMed1977

Effect of coronary bypass surgery on longevity in high and low risk patients. Report from the V.A. Cooperative Coronary Surgery Study.

There is considerable uncertainty about the effects of bypass surgery on the longevity of patients with coronary-artery disease and angina. The Cleveland Clinic has reported improved survival after surgical treatment; the Duke University study indicated improvement in a high-risk subgroup only. The Veterans Administration (V.A.) randomised study initially reported improved survival only for patients with significant left main artery (L.M.) disease. Further analysis of the V.A. study shows that survival in the high-risk subgroup was 87% for the surgically treated patients and 74% for those treated medically--a highly significant difference after four years of follow-up. However, exclusion of the L.M. group reduced the difference to a non-significant one of 84% versus 79%. For patients not in the high-risk subgroup, survival at four years (with L.M. excluded) was 93% for those treated surgically and 96% for those treated medically. For all patients the rates were 85% and 86%, respectively. These findings indicate that in the evaluation of the effects of bypass surgery on longevity the characteristics of the coronary-artery disease are critical.

Angina Pectoris↗
PubMed1976

Effect of lithium on cardiovascular performance: report on extended ambulatory monitoring and exercise testing before and during lithium therapy.

To assess the effect of long-term lithium therapy on cardiac arrhythmias and cardiovascular performance, extended ambulatory electrocardiographic monitoring was performed in 12 patients, and rest and exercise electrocardiograms in 10 of 12, before and during lithium therapy. Lithium increased the frequency of premature ventricular contractions in three patients, decreased it in one, and produced no change in eight. Three of four patients with atrial arrhythmias showed improvement during lithium therapy. Exercise performance was unchanged. Although 7 of the 12 patients manifested T wave flattening in the resting electrocardiogram, none had S-T segment displacement at rest or on treadmill exercise. Before lithium therapy, arrhythmias on exercise included premature atrial contractions in four patients, ventricular arrhythmias in four (premature ventricular contractions in four, with couplets in two and with ventricular tachycardia in one). During lithium therapy, exercise did not provoke premature atrial contractions or ventricular tachycardia in any of the patients, but three patients had premature ventricular contractions (with couplets in one case). We conclude that lithium at therapeutic levels may precipitate or aggravate ventricular arrhythmias. When administered to patients with heart disease, factors that interfere with renal clearance of lithium (heart failure, salt restriction, long-term diuretic therapy) must be recognized and doses must be adjusted accordingly. Careful follow-up and electrocardiographic monitoring are advisable if lithium is to be used in the presence of ventricular arrhythmias. Cardiovascular performance as assessed by treadmill exercise testing was not affected by long-term lithium therapy.

Adult↗