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Biomedical subjects

G O Hartzler

Publications and source records attributed to G O Hartzler.

At least 37 records · Page 2Linked to original sources
PubMed1992

Myocardial salvage with direct coronary angioplasty for acute infarction.

To assess the changes in myocardial function following direct coronary angioplasty, we evaluated 323 consecutive patients undergoing coronary angioplasty without antecedent thrombolytic therapy for acute myocardial infarction. Left ventricular function was evaluated using contrast ventriculography immediately preangioplasty and at the time of predismissal follow-up angiography (a mean of 7 days after infarction). The global ejection fraction increased from 52.6% to 58.9% (p less than 0.0005). Multivariate correlates of improved global left ventricular function included baseline ejection fraction less than or equal to 45%, and a patent infarct vessel at the time of predischarge follow-up angiography. Systolic function in the infarct zone improved by a mean of 30%. Logistic regression analysis identified sustained infarct vessel patency and anterior myocardial infarction as multivariate correlates of improved regional function in the infarct zone. In patients presenting with baseline ejection fractions less than or equal to 40%, the mean ejection fraction increased from 28% to 42%. Long-term survival was compromised in patients with global ejection fractions of less than or equal to 40% at the time of dismissal. Thus significant improvement in left ventricular function can be expected in the majority of patients undergoing direct infarct angioplasty. The myocardial salvage appears to be most significant in patients suffering large infarctions, and in those with sustained infarct vessel patency.

Aged↗
PubMed1992

Abrupt vessel closure after directional coronary atherectomy. The U.S. Directional Atherectomy Investigator Group.

From October 1, 1986 to December 31, 1989 directional coronary atherectomy was performed during 1,020 procedures (1,140 lesions) at 14 clinical centers. Abrupt vessel closure, defined as a total coronary occlusion or subtotal occlusion associated with clinical evidence of myocardial ischemia, occurred in 43 procedures (4.2%). It developed in the catheterization laboratory in 34 patients, but was delayed 1 to 96 h after directional atherectomy in 9 patients. By univariate analysis the incidence of abrupt closure was higher in directional atherectomy of de novo lesions (p less than 0.001), lesions in the right coronary artery (p = 0.001) and diffuse lesions (p = 0.04). The incidence of abrupt closure tended to be lower in directional atherectomy of saphenous vein grafts as opposed to native coronary arteries (1.6% vs. 4.4%; p = 0.08). Clinical findings during abrupt closure included severe angina in 26 patients, myocardial infarction in 17 patients, hypotension in 5 patients and death in 2 patients. Balloon angioplasty was attempted in 32 patients after abrupt vessel closure. In 16 patients balloon angioplasty resulted in initial resolution of the closure episode, although 1 patient died 96 h after the procedure. Fifteen of 16 patients without initial improvement after balloon angioplasty underwent coronary bypass operation; 9 additional patients with abrupt closure were referred directly for bypass operation. It is concluded that abrupt vessel closure develops relatively infrequently after directional coronary atherectomy. In the absence of severe coronary dissection, abrupt closure after directional atherectomy may be effectively managed with balloon angioplasty in some cases, although coronary bypass operation is often required.

Adult↗
PubMed1992

Ineffectiveness of colchicine for the prevention of restenosis after coronary angioplasty.

Colchicine, an antimitogenic agent, has shown promise in preventing restenosis after coronary angioplasty in experimental animal models. A prospective trial was conducted involving 197 patients randomized in a 2:1 fashion to treatment with oral colchicine, 0.6 mg twice daily (130 patients), or placebo (67 patients) for 6 months after elective coronary angioplasty. Treatment in all patients began between 12 h before angioplasty and 24 h after angioplasty. Compliance monitoring revealed that 96% of all prescribed pills were ingested. Demographic characteristics were similar in colchicine- and placebo-treated groups. A mean of 2.7 lesions/patient were dilated. Side effects resulted in a 6.9% dropout rate in the colchicine-treated patients. Complete quantitative angiographic follow-up was obtained in 145 patients (74%) with 393 dilated lesions. Quantitative angiographic measurements were obtained in two orthogonal views at baseline before angioplasty and immediately and at 6 months after angioplasty. The quantitative mean lumen diameter stenosis before angioplasty was 67% both in the 152 lesions in the placebo-treated group and in the 241 lesions in the colchicine-treated group; this value was reduced to 24% immediately after angioplasty in the lesions in both treatment groups. At the 6-month angiogram, lesions had restenosed to 47% lumen diameter narrowing in the placebo-treated group compared with 46% in the colchicine-treated group (p = NS). Forty-one percent of colchicine-treated patients developed restenosis in at least one lesion compared with 45% of the placebo-treated group (p = NS). In conclusion, colchicine was ineffective for preventing restenosis after coronary angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed1991

Results of multivessel percutaneous transluminal coronary angioplasty in persons aged 65 years and older.

Between 1981 and 1990, 1,373 patients, aged greater than or equal to 65 years (mean 71.2 +/- 4.9), underwent 1,640 multivessel percutaneous transluminal coronary angioplasty (PTCA) procedures. Of these, 224 patients (13.6%) had a left ventricular ejection fraction less than or equal to 40%, 412 (25.1%) had prior coronary artery bypass grafting (CABG) and 48 (2.9%) had left main artery dilatation. Of the 1,640 PTCA procedures, 697 were in patients with 2-vessel disease and 943 were in patients with 3-vessel disease. A mean 3.5 lesions were dilated per patient, with an overall angiographic success rate of 96%. Complete revascularization was achieved in 857 (52%). A total of 52 patients (3.2%) had a major in-hospital complication: 27 patients (1.6%) died, 24 (1.4%) had a Q-wave myocardial infarction, and 14 (0.8%) underwent emergent CABG. Stepwise logistic regression analysis identified ejection fraction less than or equal to 40% (p less than or equal to 0.001), 3-vessel disease (p less than or equal to 0.01), female gender (p less than or equal to 0.02), and PTCA between 1981 and 1985 (p less than or equal to 0.05) as independent predictors of mortality. Of the 1,373 patients, 1,023 have been followed for greater than or equal to 1 year (mean follow-up 32.5 +/- 21.3 months). There were 156 (15.2%) late deaths, 81 (7.9%) recurrent myocardial infarctions, and 162 (15.8%) coronary artery bypass operations. Actuarial survival, computed from the time of hospital discharge, was 92% at 1 year, 86% at 3 years and 78% at 5 years. Repeat PTCA was required in 371 patients (36.3%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Effects of diltiazem on complications and restenosis after coronary angioplasty.

A randomized, placebo-controlled, double-blinded trial was performed to evaluate the usefulness of empiric therapy with a calcium antagonist in patients who undergo coronary angioplasty. A total of 201 patients were randomized to placebo or to high-dose diltiazem (mean dose, 329 mg/day). Treatment began 24 hours before angioplasty. Restenosis was assessed by percent area stenosis as determined by quantitative angiographic techniques before, immediately and 1 year after angioplasty. All patients also received aspirin and dipyridamole before angioplasty. Heparin and verapamil were administered intravenously during the procedure. The 2 groups were similar with respect to age, extent of coronary artery disease, smoking history, and baseline lipid levels. Procedural complications, including death (1 vs 1), Q-wave infarction (0 vs 3), acute occlusion (5 vs 5) and focal spasm (0 vs 0), were not significantly different in the diltiazem and placebo patients, respectively. Freedom from all acute complications was noted in 85% of patients in both groups. One-year angiographic follow-up was obtained in 60% of patients. Restenosis rates were similar: 36% in the diltiazem group and 32% in the placebo group (p = 0.30). The incidence of late cardiac events (death, Q-wave myocardial infarction, recurrent angina or coronary bypass graft surgery) was similar in the 2 groups. Thus, diltiazem did not influence the overall restenosis rate or prevent late events after coronary angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed1991

Safety and cost effectiveness of combined coronary angiography and angioplasty.

If coronary angioplasty can be safely performed at the time of the initial diagnostic catheterization, it may result in shorter hospitalization stays and lower overall costs. Combined coronary angiography and angioplasty was performed electively on 733 patients between January 1, 1984, and September 1, 1988. These patients were divided into three major subgroups based upon their indications for angioplasty: 444 (61%) procedures were performed for restenosis; 190 (26%) procedures were performed in patients for unstable angina; and 99 (13%) procedures were performed in patients without unstable angina or previous angioplasty. A subset of 219 patients from this study who underwent elective combined coronary angiography and angioplasty during 1986 were compared with a matched population of 191 patients from the angiography and angioplasty as separate procedures). The success and complication rates were similar for both of these groups. Patients who underwent the combined procedure were hospitalized for a mean of 4.6 days with average total charges of $11,128, compared with 8.0 days and $13,160 for patients undergoing separate procedures (p less than 0.001). Significant savings were also realized with respect to total contrast dose, fluoroscopic time, and total procedural time. Thus in informed patients with suitable coronary anatomy, the strategy of combined angiography and angioplasty may present an opportunity for decreasing hospitalization stay, reducing total charges for revascularization, and reducing radiation exposure without compromising the safety or effectiveness of the procedure.

Aged↗
PubMed1991

Operative procedures not involving the heart after percutaneous transluminal coronary angioplasty.

The benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease (CAD) who require extensive surgical procedures not involving the heart has been established. During the past decade, percutaneous transluminal coronary angioplasty (PTCA) has been developed as an alternative therapy to CABG for patients with CAD. In an attempt to determine the safety of other surgical procedures after PTCA, we retrospectively reviewed 148 patients who underwent 193 surgical procedures from four to 1,867 days after PTCA for CAD. Seventy-two patients had surgical treatment within 90 days of PTCA. Thirty-five patients had CABG prior to PTCA, and 113 had PTCA as the initial treatment for CAD. Four patients died postoperatively, only one death was cardiac in origin. One patient had a myocardial infarction postoperatively (the one cardiac death). Fifteen patients had other cardiac complications (nine patients with arrhythmias and six with myocardial ischemia). Patients operated upon within 90 days of PTCA had no increased cardiac morbidity, although the one myocardial infarction occurred in this group. No difference in cardiac morbidity occurred in patients with multivessel CAD treated by PTCA compared with single vessel disease. However, patients more than 60 years of age had more cardiac problems (16 of 110) than those less than 60 years of age (zero of 38) (p = 0.01). Treatment of CAD by PTCA protects the myocardium from fatal cardiac events and myocardial infarction during subsequent noncardiac operative procedures even early (less than 90 days) in the post-PTCA period. Older patients seem to be at higher risk, however, for nonfatal cardiac complications.

Abdomen↗
PubMed1990

Timing and mechanism of in-hospital and late death after primary coronary angioplasty during acute myocardial infarction.

The effect of early myocardial reperfusion on patterns of death after acute myocardial infarction (AMI) is unknown. Thus, the mechanism and timing of in-hospital and late deaths among a group of 614 patients treated with coronary angioplasty without antecedent thrombolytic therapy for AMI were determined. Death occurred in 49 patients (8%) before hospital discharge. Four patients died in the catheterization laboratory. Death was due to cardiogenic shock in 22 patients, acute vessel reclosure in 5 patients, was sudden in 8 patients and followed elective coronary artery bypass surgery in 8 patients. Cardiac rupture was observed in only 2 patients after failed infarct angioplasty, and did not occur among the 574 patients with successful infarct reperfusion. Intracranial hemorrhage did not occur. Multivariate predictors of in-hospital death included failed infarct angioplasty, cardiogenic shock, 3-vessel coronary artery disease and age greater than or equal to 70 years. During a follow-up period of 32 +/- 21 months (range 1 to 87), 55 patients died. The cause of death was cardiac in 36 patients, including an arrhythmic death in 23 patients and was due to circulatory failure in 13 others. One patient died of reinfarction due to late reclosure of the infarct artery. Actuarial survival curves demonstrated overall survival after hospital discharge of 95 and 87% at 1 and 4 years, respectively. Freedom from cardiac death at 1 and 4 years was 96 and 92%. Multivariate predictors of late death included 3-vessel disease, a baseline ejection fraction of less than or equal to 40%, age greater than 70 years and female gender.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Early postoperative balloon coronary angioplasty for failed coronary artery bypass grafting.

In a small number of patients, coronary artery bypass grafting (CABG) fails to relieve anginal symptoms. The usefulness of coronary angioplasty for the treatment of early (less than or equal to 90 days) recurrent ischemia after CABG was examined. Forty-five patients were treated from 2 to 90 days after CABG, including 8 patients studied emergently for prolonged ischemic symptoms. One-, 2- and 3-vessel native disease was found in 4, 10 and 31 patients, respectively. At the time of postoperative angiography, the major anatomic mechanism of recurrent ischemia was complete vein graft occlusion in 12 patients (27%), internal mammary artery occlusion in 3 (7%), vein graft stenoses in 13 (29%), internal mammary artery stenoses in 10 (22%), unbypassed disease in 4 (8%) and disease distal to the graft insertion site in 3 (7%). Angioplasty was successful at 91 of 98 sites (93%), including 95% of 41 lesions in native arteries, 89% of 46 lesions in vein grafts and 100% of 11 internal mammary artery lesions attempted. Complete revascularization was achieved in 84% of patients. There were 2 in-hospital deaths and 2 myocardial infarctions. Two additional patients underwent repeat CABG before discharge after uncomplicated but unsuccessful angioplasty. At late follow-up of the 43 survivors (mean 44 months), there were 4 deaths, 2 of which were noncardiac. Repeat CABG was required in only 3 patients and repeat angioplasty was performed in 10. Angina was absent or minimal in 35 patients; 17 patients were employed full time. Thus, percutaneous transluminal coronary angioplasty can relieve myocardial ischemia after unsuccessful CABG in the majority of patients.

Adult↗
PubMed1990

Emergency percutaneous transluminal coronary angioplasty for acute myocardial infarction in patients 70 years of age and older.

Direct percutaneous transluminal coronary angioplasty (PTCA) was performed as the primary means of establishing reperfusion during acute myocardial infarction in 105 elderly patients (mean age +/- standard deviation 75 +/- 4 years) at a mean of 5.5 +/- 4.0 hours from symptom onset. Fifty-two patients (50%) had anterior infarctions, 70 (67%) had significant narrowing in greater than 1 vessel, and 12 (11%) were in cardiogenic shock. Primary success was achieved in 91% of the infarct-related arteries. Four patients with failed PTCA underwent emergency bypass surgery; 10 had early symptomatic reocclusion of the dilated vessel. There was 1 death acutely in the catheterization laboratory. The overall in-hospital mortality was 18%. Three-vessel coronary artery disease and cardiogenic shock on presentation were the strongest predictors of in-hospital death. Global ejection fraction improved from 54 +/- 13 to 61 +/- 15% (p less than 0.001). The 1- and 5-year survival rates, including in-hospital deaths, were 73 and 67%, respectively. It is concluded that direct PTCA is an effective means of salvaging ischemic myocardium during acute myocardial infarction in the elderly patient. It is associated with a high success rate and low complication rate. The short- and long-term survival in this high-risk group of patients are improved compared with survival rates in historical controls.

Aged↗
PubMed1990

Outcome following emergency coronary artery bypass grafting for failed elective balloon coronary angioplasty in patients with prior coronary bypass.

To assess frequency and outcome of emergency coronary artery bypass grafting (CABG) for failed coronary angioplasty in patients with prior CABG, 2,136 elective angioplasty procedures in prior CABG patients were reviewed over a 10-year period. Emergency surgical revascularization was required in 19 patients (0.9%) with prior CABG, compared with 130 of 6,974 patients (1.9%) without prior CABG (p = 0.001). The interval from the most recent CABG to the failed coronary angioplasty was 6.8 years (range 1 to 16). Referral for emergency CABG was made on the basis of an acute closure not responding to repeat dilatation in 12 native coronary arteries and in 7 saphenous vein grafts. Severe hemodynamic instability after acute closure required the placement of an intraaortic balloon pump in 3 patients, including 2 who required cardiopulmonary resuscitation. A total of 34 saphenous vein grafts and 1 internal mammary artery graft were placed emergently. Three patients with high-risk features (3 prior CABG operations in 1 patient, single remaining vessel to heart in 2 patients) could not be weaned from cardiopulmonary bypass. The remaining 16 patients were discharged after a mean hospital stay of 16 days. Four patients developed new Q waves after CABG. At follow-up (mean 52 months, range 3 to 99), 1 patient died late from an acute myocardial infarction. The 15 survivors had no or mild angina and were free of further CABG. Thus, emergency CABG after failed angioplasty in patients with prior CABG is required infrequently. In patients without extreme high-risk features, emergency repeat CABG can be accomplished with good hospital and long-term results.

Aged↗
PubMed1990

Usefulness of angioplasty during acute myocardial infarction in patients with prior coronary artery bypass grafting.

The efficacy and risk of reperfusion strategies for myocardial infarction in patients with prior coronary artery bypass surgery are uncertain. In this study 72 patients with prior bypass grafting underwent direct percutaneous transluminal coronary angioplasty without antecedent thrombolytic therapy. There were 26 anterior and 46 inferior infarctions, including 11 patients (15%) in cardiogenic shock. The baseline ejection fraction was less than 40% in 47 (65%) patients. Angioplasty was successful in 41 of 48 (85%) vein grafts and 24 of 24 (100%) arteries (difference not significant) at 5.1 +/- 4.0 hours from the onset of symptoms (79% treated less than 6 hours). There were no urgent bypass operations, strokes or transfusions. In-hospital survival was 90% (nonshock 95% vs shock 64%, p less than 0.01). Symptomatic acute reclosure occurred in 1 patient. Predischarge coronary arteriography in 34 patients demonstrated continued vessel patency in 32 infarct vessels (94%), although 5 of these vessels were redilated for restenoses. Predischarge paired ventriculography in 26 patients showed an increase in ejection fraction from 44 +/- 16% to 51 +/- 18% (p less than 0.01). One- and 3-year actuarial survival was 89 and 87%. Thus, prior coronary surgery should not preclude reperfusion therapy by direct angioplasty, which can be accomplished with low procedural risk, improvements in ventricular function and excellent in-hospital and late survival.

Aged↗
PubMed1990

Procedural outcome of angioplasty for total coronary artery occlusion: an analysis of 971 lesions in 905 patients.

This study analyzes the results of angioplasty in 905 consecutive patients with 971 total occlusions. The procedures were performed by five cardiologists from January 1980 to January 1989 at one institution. The overall success rate per lesion was 72%. Even the most experienced operator (524 occlusions attempted) has continued to improve on a learning curve, with 83% of his most recent 100 occlusions successfully dilated. Procedural death occurred in seven patients (0.8%), five patients (0.6%) sustained a myocardial infarction and seven patients (0.8%) required urgent coronary bypass surgery. Complications were significantly more likely to occur in the elderly, in women and in patients with triple vessel disease and depressed left ventricular function. Compared with angioplasty in 6,950 patients with nonoccluded stenoses, angioplasty of total occlusions had a lower success rate (72% versus 96%, p = 0.001), although the complication rate was also lower (1.9% versus 3.5%, p = 0.01). Multivariate analysis of 20 clinical and angiographic variables in 100 consecutive patients undergoing angioplasty of 104 total occlusions in 1988 identified only bridging collateral vessels (85% success rate if absent versus 18% if present, p less than 0.001) and a tapered occlusion morphology (88% success rate if present versus 59% if absent, p = 0.01) as independent correlates of procedural outcome. Other variables, including the estimated duration of occlusion, lesion length and location, and extent of disease were unrelated to technical success. With present techniques and sufficient operator experience, 70% to 80% of total occlusions can be successfully recanalized by coronary angioplasty with a complication rate of less than 2%.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗