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J Hollman

Publications and source records attributed to J Hollman.

At least 19 recordsLinked to original sources
PubMed1993

Effects of stent design and serum cholesterol level on the restenosis rate in atherosclerotic rabbits.

We investigated the effect of serum cholesterol level and stent design on the restenosis rate within the stent after balloon angioplasty and stent implantation using atherosclerotic rabbits. Two types of nickel/titanium stents with gaps (open stent) and without gaps (closed stent) between the wire coils were implanted into the aorta of the rabbits 10 weeks after atherosclerosis had been induced using a standard high cholesterol diet and balloon abrasion. Each rabbit had an open stent and a closed stent implanted into the infrarenal abdominal aorta. Between these two stents a control segment of the aorta was treated with angioplasty alone. The animals were divided into two groups according to the diet protocol as follows: in group I (n = 9) a high cholesterol diet was stopped after stent implantation; in group II (n = 10) a high cholesterol diet was maintained after stent implantation. Digital subtraction angiograms were obtained every 4 weeks for up to 24 weeks and the narrowest diameter of the arterial segments within each stent and in the segment between stents was measured. The diameter narrowing within the closed stent was greater in the high cholesterol group compared with the low cholesterol group: 12 weeks (2.57 +/- 0.09 mm in group I vs 2.14 +/- 0.15 mm in group II, mean +/- S.E., p < 0.05); 16 weeks (2.55 +/- 0.09 mm vs 2.14 +/- 0.12 mm, p < 0.05); 20 weeks (2.59 +/- 0.06 mm vs 1.98 +/- 0.12 mm, p < 0.01); and 24 weeks (2.45 +/- 0.11 mm vs 2.01 +/- 0.11 mm, p < 0.05). No significant differences in the narrowest diameter of the arterial segments were observed between high and low cholesterol groups in the angioplasty alone areas or within the open stents. There was a significant difference in the narrowest diameter between stents with versus those without gaps (at 12, 16, and 20 weeks poststenting in group I and at 4, 8, 12, 16, 20, and 24 weeks in group II). Thus the stent with the least metal is correlated with less stenosis and intimal hyperplasia. From these data we conclude that both stent design and serum cholesterol are important factors for restenosis after stent implantation.

Angioplasty, Balloon, Coronary↗
PubMed1992

Effects of design geometry of intravascular endoprostheses on stenosis rate in normal rabbits.

To investigate the effects of gaps between the individual wire coils of a shape memory Nitinol alloy intravascular endoprosthesis, 20 stents with and without gaps were implanted transluminally into the infrarenal abdominal aortas of 10 normal rabbits after balloon angioplasty. Digital subtraction angiography (DSA) was done at 4, 12, 16, 20, and 24 weeks after stent implantation to examine the stenosis rate and major side branch patency. Stenosis rate within stents with gaps were significantly lower than those without gaps: 8.1 +/- 5.0% versus 15.0 +/- 6.8% at 12 weeks, 13.6 +/- 6.0% versus 26.0 +/- 9.4% at 24 weeks by DSA, p greater than 0.005 and p less than 0.01 respectively. The maximum and mean neointimal thickness measured histologically at the time of animal death correlated significantly to the narrowest diameter obtained from the DSA studies, (r = 0.84 and r = 0.79, respectively, p less than 0.01). Greater hyperplasia of the neointima was evident in the stented arterial segments with stents without gaps compared with those with gaps (83 +/- 22 versus 187 +/- 46 microns mean thickness, p less than 0.001). The patency rate of the side branches in the stented arterial segment was significantly (p less than 0.05) higher in stents having gaps. These results suggest that the placement of gaps between wire pitches reduced the neointimal thickness within stents and prevented the obstruction of arterial side branches.

Angioplasty, Balloon↗
PubMed1992

Multivessel and single-vessel coronary angioplasty: a comparative study.

To determine the efficacy of multivessel coronary angioplasty, 569 consecutive patients undergoing multivessel angioplasty were compared with 569 age- and sex-matched control patients undergoing single-vessel angioplasty. Baseline variables were similar except for number of diseased vessels and greater left ventricular dysfunction in the multivessel group. Major in-hospital complication rates (death, 0% vs 0.5%; Q wave myocardial infarction, 0.5% vs 0.9%; emergency bypass surgery, 2.5% vs 3.2%) were similar for multivessel and single-vessel angioplasty. The 5-year actuarial survival rate was 93% for multivessel angioplasty and 92% for single-vessel angioplasty. Event-free survival was similar except that patients undergoing multivessel angioplasty had an 8% higher incidence of repeat coronary angioplasty in the first year of follow-up (p = 0.03). Multivessel coronary angioplasty can be performed with results comparable to those of single-vessel angioplasty with the exception of a higher incidence of repeat angioplasty.

Actuarial Analysis↗
PubMed1990

Restenosis after transluminal coronary angioplasty: a risk factor analysis.

In order to determine the relationship of restenosis following percutaneous transluminal coronary angioplasty (PTCA) to risk factors such as hypercholesterolemia, hyperglycemia, smoking, and weight, we performed a univariate analysis to test the association of these variables with restenosis in 723 patients who had percutaneous transluminal coronary angioplasty and follow-up catheterization. Cholesterol levels were higher in younger and female subjects (less than 0.0001). Initial cholesterol did not predict restenosis, and follow-up cholesterol levels showed an inverse relationship with restenosis (P less than .02). There was a trend (P less than .09) toward decreased restenosis in those who were active smokers at the time of follow-up catheterization. No differences were seen in diabetics with hyperglycemia, in both treated and untreated groups (P = NS). A stepwise multiple logistic regression was used to simultaneously test the association of the above risk factor variables to restenosis. None of the interactions were found to be significant, except cholesterol at follow-up (P = .001). Therefore, the status of serum cholesterol, blood sugar, smoking, and weight during the time of PTCA and at follow-up catheterization may be unimportant in predicting restenosis. Thus, we conclude 1) that to better determine the effect of these variables on restenosis, they should be estimated at times other than follow-up and 2) that the pathophysiological mechanism of restenosis may have different risk factors than progression of atherosclerotic coronary artery disease.

Angioplasty, Balloon, Coronary↗
PubMed1990

Acute myocardial infarction associated with intravenous dipyridamole for rubidium-82 PET imaging.

This report describes the occurrence of chest pain and electrocardiographic features of acute myocardial infarction following intravenous dipyridamole-handgrip stress. Myocardial perfusion imaging (Rb-82 PET) demonstrated a stress-induced perfusion defect. Following failure to respond to medical therapy, urgent cardiac catheterization demonstrated total occlusion of the left anterior descending coronary artery. The vessel was revascularized, with limitation of myocardial damage evidenced by failure to develop anterior Q waves and only modest elevation of cardiac enzyme levels. Complications of intravenous dipyridamole stress are rare, this case constituting the first major problem in over 500 such procedures at this institution. However, this experience demonstrates the importance of vigilant observation during the performance of this technique.

Dipyridamole↗
PubMed1990

Long-term outcome of unsuccessful percutaneous transluminal coronary angioplasty.

We analyzed the long-term outcome of 198 patients after unsuccessful percutaneous transluminal coronary angioplasty. Forty-nine percent underwent emergency coronary artery bypass grafting surgery, 17% had elective bypass surgery, and 34% were treated medically. The in-hospital mortality rate was 4%, and myocardial infarction occurred in 36% of patients. Follow-up was completed in 100% of patients with a mean follow-up period of 35 +/- 22 months. Actuarial cardiac survival at 4 years was 97% in the emergency bypass surgery group, 100% in the elective bypass surgery group, and 86% in the medically treated group. Actuarial event-free survival (freedom from myocardial infarction, bypass surgery, coronary angioplasty, and cardiac death) at 4-year follow-up was 81% in 198 patients, 90% in the emergency bypass surgery group, 85% in the elective bypass surgery group, and 65% in the medically treated group. Results of multivariate analysis showed that emergency or elective bypass surgery after failed coronary angioplasty, normal or mildly impaired left ventricular function, and male sex were predictors of better outcome at 4 years.

Actuarial Analysis↗
PubMed1990

Percutaneous transluminal coronary angioplasty in silent ischemia.

The short- and long-term outcome of percutaneous transluminal coronary angioplasty were analyzed in 34 patients who had documented coronary artery disease without symptoms. Of the 34 patients, 33 had abnormal stress tests before angioplasty. Angioplasty was successful in 31 patients (91%). Follow-up was 100% for a mean period of 36 +/- 15 months. Follow-up exercise test was normal or improved in 29 of the 31 patients who had successful angioplasty. Follow-up catheterization was performed in 24 of the 31 patients (77%). Restenosis of the previously dilated segment was found in seven patients. Actuarial cardiac survival at 3 years was 100%. Freedom from myocardial infarction, bypass surgery, angioplasty for a new lesion, and death was 87%. We conclude that although the most effective treatment for silent ischemia remains to be determined, our data suggest that coronary angioplasty is a therapeutic option in these patients.

Actuarial Analysis↗
PubMed1990

Vascular stenting in normal and atherosclerotic rabbits. Studies of the intravascular endoprosthesis of titanium-nickel-alloy.

Percutaneous transluminal balloon angioplasty would be more effective if the rate of recurrent stenosis were reduced. To evaluate the prevention of restenosis after percutaneous transluminal angioplasty, intravascular endoprosthetic stents of titanium-nickel-alloy were implanted transluminally in seven normal and 21 atherosclerotic rabbits. In normal rabbits, a 3.5-mm diameter stent was implanted in the aorta and a 2.5-mm diameter stent in the right iliac artery, which were followed with serial angiograms from 6 weeks (n = 7) to 8 months (n = 4). There was a mean stenosis of 13.1% in the 2.5-mm and 13.6% in the 3.5-mm stent. There was no significant narrowing compared with the adjacent control segments of artery; histopathology showed a thin, fibrous neointima with smooth muscle cells. Each atherosclerotic rabbit was balloon dilated at two separate stenotic sites; each site was 2.0 cm in length. The aortic site (with 28.8 +/- 13.8% mean stenosis [+/- SD]) was dilated with a 3.5-mm balloon, and the iliac site (with 36.5 +/- 14.2% stenosis) was dilated with a 2.5-mm balloon. In each site, an intravascular stent of corresponding diameter and 7-mm length was implanted in one half of the dilated segment, assigned randomly, and the other half served as the angioplasty control. Angiographically observed restenosis rates and the corresponding histopathology were similar in the atherosclerotic segments that had angioplasty alone versus the atherosclerotic segments that had angioplasty plus stenting. The mean neointimal thickness in the aortas and iliac arteries, respectively, measured 247 +/- 181 microns (+/- SD) and 218 +/- 77 microns after 6 weeks (n = 8) versus 321 +/- 168 and 308 +/- 189 microns after 20 weeks (n = 5, p = NS). At 20 weeks follow-up, there was 29.1 +/- 29.8% (median, 16.4%) stenosis in the aortic stent versus 38.9 +/- 24.1% (median, 34.0%) stenosis in the percutaneous transluminal angioplasty control segment of aorta (n = 5, p = NS) and 81.4 +/- 25.5% stenosis in the iliac artery stent versus 89.3 +/- 15.3% stenosis in the PTA control segment of the right iliac artery (n = 5, p = NS). Comparing stenotic arterial segments treated with angioplasty alone with angioplasty plus intravascular stenting in the atherosclerotic rabbits showed that there was no significant difference in either the histopathologic changes or the restenosis rates.

Alloys↗
PubMed1989

Changing patterns in percutaneous transluminal coronary angioplasty.

We analyzed the impact of evolving technology on percutaneous transluminal coronary angioplasty in 2677 patients. There were 168 patients in period 1 when fixed-wire catheters were used, 1117 patients in period 2 when steerable catheters were available, and 1392 patients in period 3 when low-profile systems were utilized. The age of patients (55 to 57 to 59 years) and the proportion of patients with severe angina increased over the three periods (25% to 36% to 54%). The percentage of high-grade stenosis and the proportion of distal lesions also increased. Primary success rate improved from 73% in period 1 to 94% in periods 2 and 3. Emergency bypass surgery decreased (8.3% to 4.2% to 2.5%), as did the incidence of myocardial infarction (7.1% to 3.3% to 2.4%). Mortality was 0% in period 1, 0.2% in period 2, and 0.4% in period 3. These results indicate that technological advancements and increased operator experience significantly improved the primary success rate and decreased the incidence of major complications.

Angioplasty, Balloon↗
PubMed1989

Percutaneous transluminal angioplasty of saphenous vein graft stenosis: long-term follow-up.

Percutaneous transluminal angioplasty was used to treat 101 patients with saphenous vein bypass graft stenosis at a mean of 50.1 months (range 2 to 196) after coronary artery bypass surgery. The patients presented between March 1981 and April 1987. A total of 107 saphenous vein grafts were dilated at 117 sites. The primary success rate was 91.8%. The incidence of cardiac complications was 7.1%. There were no cardiac complications in 53 patients with grafts implanted less than 36 months before angioplasty (Group 1). The 48 patients with grafts implanted for greater than 36 months (Group 2) had a 12.5% incidence rate of myocardial infarction, a 4% incidence rate of emergent bypass surgery and a 4% incidence rate of death for an overall cardiac complication rate of 14.9% (p less than 0.01). Follow-up was obtained at a mean of 16.8 +/- 13.9 months (range 1 to 54) in 87 patients (97% of successful cases). Repeat coronary angiography was performed in 49 patients and revealed restenosis in 30 patients (61.2%), with no difference in recurrence rates for proximal, mid or distal graft sites. Clinical recurrence (defined as recurrence of symptoms, myocardial infarction, repeat angioplasty, surgery or death) was 33.1% for Group 1 patients and 64.1% for Group 2 patients (p less than 0.01). The complication and recurrence rates of saphenous vein graft angiography are significantly higher when performed for late (greater than 36 months) vein graft failure. All therapeutic options should be carefully examined before proceeding with angioplasty for saphenous vein graft stenosis in this type of patient.

Angioplasty, Balloon↗
PubMed1989

Acute occlusion in multiple lesion coronary angioplasty: frequency and management.

Among 3,548 patients undergoing a percutaneous transluminal coronary angioplasty procedure, 714 had multilesion angioplasty (1,550 lesions) in a single session. Acute occlusion occurred in 22 patients (3.1%) and 29 lesions (1.9%). The patients were classified into a group undergoing multivessel angioplasty (348 patients, 785 lesions) and a group undergoing multilesion single vessel angioplasty (366 patients, 765 lesions). The rate of acute occlusion was similar in both patient groups. The multivessel angioplasty group had a 2.9% rate per patient (n = 10) and a 1.7% rate per vessel; the multilesion single vessel group had a 3.3% rate per patient (n = 12) and a 2.1% rate per lesion. Five of the 10 patients from the multivessel group with acute occlusion, but only 1 of the 12 patients with occlusion in the single vessel multilesion group, required emergency open heart surgery. No patient in either group died as a consequence of coronary angioplasty. Occlusion occurred during angioplasty in 15 of the 22 patients, and 1 to 24 h after angioplasty in 7 of 22 patients. In the group with multivessel angioplasty, acute occlusion during the procedure was mainly linked with hypotension during the second vessel dilation, whereas in this group with delayed vessel closure and in the multilesion single vessel group, existence of intimal tearing constituted the most important factor for acute occlusion (12 of 16 patients). Closure of vessel per major coronary system was evenly distributed in the multivessel group, whereas significantly more left circumflex vessels closed in the single vessel multilesion group (6.1% versus 1.3% in the left anterior descending coronary artery and 1.1% in the right coronary artery; p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1989

Percutaneous transluminal coronary angioplasty in the young adult.

A total of 33 patients age 35 years or younger underwent percutaneous transluminal coronary angioplasty (PTCA) at The Cleveland Clinic Foundation between January 1981 and October 1987. Arteriography showed one-, two-, and three-vessel disease in 16, 12, and 5 patients, respectively. Twenty-four patients (73%) had functional Class 3 or 4 angina and 17 (52%) had unstable angina. PTCA was performed in one vessel each in 22 patients and in multiple vessels in 11 patients. Of 47 vessels, 44 (94%) were successfully dilated. There were no deaths, emergency bypass procedures, or myocardial infarctions during hospitalization. At a mean follow-up of 30 months, there were two late deaths, nine repeat PTCA procedures, one coronary bypass, and one nonfatal myocardial infarction. Due to the progressive nature of coronary artery disease in the young adult, PTCA appears to be a good therapeutic modality for selected patients in this age group.

Adult↗
PubMed1989

Multiple myocardial infarctions associated with atheromatous emboli after PTCA of saphenous vein grafts. A clinicopathologic correlation.

Percutaneous transluminal coronary angioplasty (PTCA) of stenotic saphenous vein grafts is less invasive than repeat coronary bypass grafting; however, this procedure is complicated by atheromatous embolization in 2.5%-3.0% of cases, an incidence significantly higher than in angioplasty of native coronary vessels. We reviewed the cases of 98 patients who underwent elective saphenous vein graft angioplasty at our institution. Five patients (5.1%) had non-Q-wave myocardial infarctions after the procedure, documented by elevated serum creatine kinase. In four, atheroembolism was suspected during the procedure. Two patients died, and autopsy showed that both had multiple atherosclerotic emboli to the distal epicardial coronary artery supplied by the vein graft. In addition, multiple infarcts of varying age, some clearly antedating the angioplasty procedure, were identified. These findings suggest that both ongoing, recurrent atheroembolism as well as angioplasty-related embolism may occur in older vein grafts.

Aged↗
PubMed1988

Determinants of primary success in elective percutaneous transluminal coronary angioplasty for significant narrowing of a single major coronary artery.

Clinical and angiographic characteristics, procedural details and outcome were analyzed in 2,677 consecutive patients who underwent elective single-artery, single-lesion percutaneous transluminal coronary angioplasty (PTCA) between December 1980 and May 1987. Primary success was achieved in 2,479 (93%) patients. The primary success rate was significantly lower during the first period, when nonsteerable systems were used (73%), than in later periods (94%) (p less than 0.0001), when steerable and low-profile systems became available. Univariate analysis revealed the following variables as predictors of lower primary success: totally obstructed arteries (p less than 0.0001), presence of calcium in the narrowing (p = 0.002), prior myocardial infarction (p = 0.005), stenoses located in the right coronary artery (p = 0.02), narrowings between 90 and 99% in diameter (p = 0.02) and patients older than 60 years of age (p = 0.07). Multivariate analysis revealed the following 4 independent predictors of lower primary success: 100% obstruction (p less than 0.0001), calcium (p = 0.005), previous myocardial infarction (p = 0.029) and patients older than 60 years of age (p = 0.036). With present technology, single-narrowing elective PTCA can be performed with a high success rate in most patients. Although total occlusion, presence of calcium, older age and history of myocardial infarction influence the outcome unfavorably, PTCA can still be performed with acceptable primary success rates.

Adult↗