Frye, Robert L.

The effect of the mitral Starr-Edwards ball-valve prosthesis on cardiac function was investigated in the dog. Fifteen dogs were studied for the first 48 hours after replacement of the mitral valve (the chordae tendineae [see Figure in the PDF file] had been totally resected, partially resected, or preserved). The cardiac output and left atrial pressure were similar in these three groups of animals and in two animals subjected to sham operation. Ten dogs (five with intact chordae and five with excised chordae) were studied two months after the insertion of a Starr-Edwards prosthesis. In these animals normal hemodynamic values were obtained at rest and during infusion of acetylcholine, except for a marked (liastolic gradient across the prosthesis, which developed at high cardiac output and heart rate. Six dogs were able to complete a standard test of substantial, unrestrained, graded exercise and gave a normal heart rate response. Heart rate increased and was maintained during maximal efforts, to levels of about 300 beats/min, demonstrating that heart rate need not be a limit of cardiac performance. No evidence of left ventricular dysfunction or of a decrement in cardiac performance could be demonstrated in dogs early or late after replacement of the mitral valve with a Starr-Edwards prosthesis. The presence or absence of chordae tendineae was irrelevant to cardiac performance.

Sixteen patients with diffuse hypertrophic subaortic stenosis have been treated surgically. Thirteen of 14 patients undergoing excision of hypertrophied muscle from the left ventricular outflow tract via left ventriculotomy or aortotomy have survived. Operation has provided excellent symptomatic relief, associated with eradication or significant reduction of the systolic pressure gradient between the left ventricle and the aorta while the patient is at rest. Operation is recommended for those patients with this disease who are experiencing significant and limiting symptoms related to obstruction of the left ventricular outflow tract.

Background —Patients with treated diabetes in the randomized-trial segment of the Bypass Angioplasty Revascularization Investigation (BARI) who were randomized to initial revascularization with PTCA had significantly worse 5-year survival than patients assigned to CABG. This treatment difference was not seen among diabetic patients eligible for BARI who opted to select their mode of revascularization. We hypothesized that differences in patient characteristics, assessed and unmeasured, together with the treatment selection in the registry, at least partially account for this discrepancy. Methods and Results —Among diabetics taking insulin or oral hypoglycemic drugs at entry, angiographic and clinical presentations were comparable between randomized and registry patients. However, more registry patients were white, and registry diabetics tended to be more educated and more physically active and to report better quality of life. Procedural characteristics and in-hospital complications were comparable. The 5-year all-cause mortality rate was 34.5% in randomized diabetic patients assigned to PTCA versus 19.4% in CABG patients ( P =0.0024; relative risk [RR]=1.87); corresponding cardiac mortality rates were 23.4% and 8.2%, respectively ( P =0.0002; RR=3.10). The CABG benefit was more apparent among patients requiring insulin. In the registry, all-cause mortality was 14.4% for PTCA versus 14.9% for CABG ( P =0.86, RR=1.10), with corresponding cardiac mortality rates of 7.5% and 6.0%, respectively ( P =0.73; RR=1.07). These RRs in the registry increased to 1.29 and 1.41, respectively, after adjustment for all known differences between treatment groups. Conclusions —BARI registry results are not inconsistent with the finding in the randomized trial that initial CABG is associated with better long-term survival than PTCA in treated diabetic patients with multivessel coronary disease suitable for either surgical or catheter-based revascularization.

Background —Surgical correction of mitral regurgitation in patients with no or mild symptoms remains controversial, particularly because the impact of preoperative symptoms on postoperative outcome is unknown. Methods and Results —The long-term outcome of 478 patients with organic mitral regurgitation (199 in NYHA functional class I/II and 279 in class III/IV before surgery) operated on between 1984 and 1991 was analyzed. In patients in NYHA class I/II before surgery compared with those in class III/IV, postoperative long-term survival was higher (at 10 years, 76±5% versus 48±4%, P <0.0001), with lower operative mortality (0.5% versus 5.4%, P =0.003) and better late survival ( P <0.0001). Comparison of observed and expected survival showed identical curves in patients in class I/II before surgery ( P =0.18), whereas excess mortality was observed in patients in class III/IV before surgery ( P <0.0001). Excess mortality associated with severe symptoms was also confirmed in all subgroups (all P <0.003) and in multivariate analysis ( P =0.0036; adjusted hazard ratio [95% CI], 1.81 [1.21 to 2.70]). Conclusions —In patients with organic mitral regurgitation, preoperative functional class III/IV symptoms are associated with excess short- and long-term postoperative mortality independently of all baseline characteristics. These data should lead to consideration of surgical correction of severe organic mitral regurgitation when no or minimal symptoms are present in patients at low operative risk, especially if repair is feasible.

Background— Coronary artery disease (CAD) is the major cause of death in patients with type 2 diabetes mellitus. Although demographic and clinical factors associated with extent of CAD in patients with diabetes mellitus have been described, genetic factors have not. We hypothesized that genetic variation in peroxisome proliferator-activated receptor (PPAR) pathway genes, important in diabetes mellitus and atherosclerosis, would be associated with extent of CAD in patients with diabetes mellitus. Methods and Results— We genotyped 1043 patients (702 white, 175 blacks) from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) genetic cohort for 3351 variants in 223 PPAR pathway genes using a custom targeted-genotyping array. Angiographic end points were determined by a core laboratory. In whites, a single variant (rs1503298) in TLL1 was significantly ( P =5.5×10 −6 ) associated with extent of CAD, defined as number of lesions with percent diameter stenosis ≥20%, after stringent Bonferroni correction for all 3351 single nucleotide polymorphisms. This association was validated in the diabetic subgroups of 2 independent cohorts, the Translational Research Investigating Underlying Disparities in Acute Myocardial Infarction Patients' Health Status (TRIUMPH) post–myocardial infarction registry and the prospective Family Heart Study (FHS) of individuals at risk for CAD. TLL1 rs1503298 was also significantly associated with extent of severe CAD (≥70% diameter stenosis; P =3.7×10 −2 ) and myocardial jeopardy index ( P =8.7×10 −4 ). In general linear regression modeling, TLL1 rs1503298 explained more variance of extent of CAD than the previously determined clinical factors. Conclusions— We identified a variant in a single PPAR pathway gene, TLL1 , that is associated with the extent of CAD independently of clinical predictors, specifically in patients with type 2 diabetes mellitus and CAD. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00006305.

Background— Effects were compared in patients in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial of 2 mechanistically different strategies for treatment of hyperglycemia, insulin-sensitizing and insulin-providing strategies, on biomarker profiles reflecting the balance between fibrinolysis and thrombosis and the intensity of inflammation implicated in diabetic vasculopathy. Methods and Results— A total of 2368 patients with type 2 diabetes mellitus and clinically stable, angiographically documented coronary artery disease were randomized to treatment with 1 of the 2 strategies and followed for an average of 5 years. Plasminogen activator inhibitor type 1 antigen and activity, tissue plasminogen activator antigen, fibrinogen, D-dimer, C-reactive protein, insulin, and hemoglobin A 1c were assayed in blood samples acquired at baseline and at 12 regular intervals throughout the follow-up interval. Higher baseline D-dimer, fibrinogen, and C-reactive protein portended a poor prognosis in patients in both groups. In contrast to the insulin-providing strategy, the insulin-sensitizing strategy led to (1) lower plasma insulin; (2) lower plasminogen activator inhibitor type 1 antigen and activity and lower tissue plasminogen activator antigen (known to track with plasminogen activator inhibitor type 1); and (3) lower C-reactive protein and fibrinogen at all intervals after baseline ( P <0.001 for each). Conclusions— The insulin-sensitizing treatment strategy led to changes in biomarker profiles indicative of decreased insulin resistance, an altered balance between thrombosis and fibrinolysis favoring fibrinolysis, and diminished intensity of the systemic inflammatory state, factors that have been associated with cardiovascular risk. Clinical Trial Registration— http://www.clinicaltrials.gov . Unique identifier: NCT00006305.

This is a study of cardiac diseases associated with the 1,382 cases of first cerebral infarction in residents of Rochester, Minn., during 1960-1984. This is a population-based study in Rochester, Minn., for which the medical record-linkage system was used to identify cardiac disease among patients with first cerebral infarction. There were 318 patients (23%) who had at least one major potential cardiac source of emboli. The proportion of patients with a cardiac source of emboli was significantly higher among patients older than age 75 years (29%) than among younger patients (17%). The 30-day stroke recurrence rate among patients with a cardiac source of emboli (2%) was not significantly different than that among those without a cardiac source of emboli (2%). Among patients with a cardiac source of emboli, there was no difference in the probability of stroke at 30 days and at 90 days for those treated or not treated with anticoagulants. During the first 30 days after cerebral infarction, the risk of death in patients with a cardiac source of emboli (23%) was 14 times that of recurrent stroke. The risk of death at 30 days in patients without a cardiac source of emboli was 8%. Significant independent predictors of death (Cox proportional-hazards analysis) were age, prior myocardial infarction, atrial fibrillation present at onset of stroke, congestive heart failure before the stroke, and an age x congestive heart failure interaction. The only significant independent predictors of recurrent stroke were cardiac valve disease and congestive heart failure.