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M J Cowley

Publications and source records attributed to M J Cowley.

At least 19 recordsLinked to original sources
PubMed2001

Results of the study to determine rotablator and transluminal angioplasty strategy (STRATAS).

Rotational atherectomy is used to debulk calcified or complex coronary stenoses. Whether aggressive burr sizing with minimal balloon dilation (<1 atm) to limit deep wall arterial injury improves results is unknown. Patients being considered for elective rotational atherectomy were randomized to either an "aggressive" strategy (n = 249) (maximum burr/artery >0.70 alone, or with adjunctive balloon inflation < or = 1 atm), or a "routine" strategy (n = 248) (maximum burr/artery < or =0.70 and routine balloon inflation > or =4 atm). Patient age was 62 +/- 11 years. Fifty-nine percent routine and 60% aggressive strategy patients had class III to IV angina. Fifteen percent routine and 16% aggressive strategy patients had a restenotic lesion treated; lesion length was 13.6 versus 13.7 mm. Reference vessel diameter was 2.64 mm. Maximum burr size (1.8 vs 2.1 mm), burr/artery ratio (0.71 vs 0.82), and number of burrs used (1.9 vs 2.7) were greater for the aggressive strategy, p <0.0001. Final minimum lumen diameter and residual stenosis were 1.97 mm and 26% for the routine strategy versus 1.95 mm and 27% for the aggressive strategy. Clinical success was 93.5% for the routine strategy and 93.9% for the aggressive strategy. Creatine kinase-myocardial band (CK-MB) was >5 times normal in 7% of the routine versus 11% of the aggressive group. CK-MB elevation was associated with a decrease in rpm of >5,000 from baseline for a cumulative time >5 seconds, p = 0.002. At 6 months, 22% of the routine patients versus 31% of the aggressive strategy patients had target lesion revascularization. Angiographic follow-up (77%) showed minimum lumen diameter to be 1.26 mm in the routine group versus 1.16 mm in the aggressive group, and the loss index 0.54 versus 0.62. Dichotomous restenosis was 52% for the routine strategy versus 58% for the aggressive strategy. Multivariable analysis indicated that left anterior descending location (odds ratio 1.67, p = 0.02) and operator-reported excessive speed decrease >5,000 rpm (odds ratio 1.74, p = 0.01) were significantly associated with restenosis. Thus, the aggressive rotational atherectomy strategy offers no advantage over more routine burr sizing plus routine angioplasty. Operator technique reflected by an rpm decrease of >5,000 from baseline is associated with CK-MB elevation and restenosis.

Aged↗
PubMed2000

Ad hoc coronary intervention.

Ad hoc coronary intervention is a percutaneous revascularization procedure performed at the same sitting as diagnostic cardiac catheterization. While this appears to be an efficient strategy, the safety and cost of ad hoc coronary intervention compared with delayed coronary intervention have not been clearly documented. Special preparation and precautions are necessary for patients in whom ad hoc coronary intervention is anticipated. Ad hoc coronary intervention is not appropriate if informed consent has not been previously obtained or if it would pose greater risks than delayed intervention. While ad hoc coronary intervention is often efficient and effective, its use should be individualized. Cathet. Cardiovasc. Intervent. 49:130-134, 2000.

Cardiac Catheterization↗
PubMed1999

Percutaneous revascularization modalities in heart transplant recipients.

Accelerated allograft vasculopathy significantly limits the survival of heart transplant recipients. The prevalence of allograft coronary artery disease is as high as 18% by 1 year and 50% by 5 years following heart transplant. Heart failure and sudden cardiac death are the two most common clinical presentations. In heart transplant recipients with severe, discrete focal allograft vascular disease, percutaneous balloon angioplasty is a viable palliative option. However, its application is limited by a significant restenosis rate and progression of allograft disease in nontreated segments. Diffuse disease with tapering of vessels may be approached by debulking devices. Emerging revascularization modalities for focal stenoses and some of the diffuse tapering vessels include coronary stents, rotational atherectomy, various wavelength lasers, and, to a lesser extent, directional atherectomy. Conceivably, stents will reduce restenosis rates related to focal, discrete plaques; yet it is unknown whether they will be efficacious in short- and long-term treatment of diffusely diseased segments affected by allograft disease. Accurate assessment of clinical outcomes and long-term evaluation is imperative prior to acceptance of these devices as fundamental interventional tools for treatment of allograft coronary artery disease.

Adult↗
PubMed1998

Balloon angioplasty versus new device intervention: clinical outcomes. A comparison of the NHLBI PTCA and NACI registries.

OBJECTIVES: We sought to compare outcomes of patients treated in the National Heart, Lung, and Blood Institute (NHLBI) Percutaneous Transluminal Coronary Angioplasty (PTCA) and New Approaches to Coronary Intervention (NACI) registries. BACKGROUND: Coronary angioplasty has numerous shortcomings. New devices for performing coronary interventions have been introduced in an effort to improve clinical outcomes. METHODS: Under the sponsorship of the NHLBI, a registry of consecutive patients treated with PTCA during 1985 to 1986 was established. In 1990, the NHLBI funded a second registry, the NACI. The two registries used the same data coordinating center to collect detailed baseline and follow-up information. RESULTS: Patients enrolled in the NACI registry were older, had undergone more previous bypass surgery procedures and had more stenoses located in bypass grafts than patients in the NHLBI PTCA registry. Procedural success was achieved in 72.1% and 82.6% of patients in the PTCA and NACI registries, respectively; however, in-hospital and 1-year mortality rates were 1.0% versus 1.8% and 3.1% versus 5.9% for the PTCA versus NACI registries, respectively. After risk adjustment, there was no difference in 1-year mortality. Rates of target lesion revascularization (TLR) were 21.5% for the PTCA registry and 24.2% for the NACI registry. NACI registry patients had a higher risk for TLR and the composite end point of death, myocardial infarction or revascularization (relative risk 1.28 and 1.23, respectively). However, the NACI registry patients who received stents tended to have a lower adjusted TLR rate. CONCLUSIONS: This comparative study found no overall superiority of these newer devices in terms of patient survival or freedom from TLR after adjustment for baseline risk profiles. Although technologic improvements (especially improved stenting) continue, these observations highlight the importance of careful assessment of clinical results in the broad population of patients in whom interventions are used.

Angioplasty, Balloon, Coronary↗
PubMed1997

Influence of gender on in-hospital clinical and angiographic outcomes and on one-year follow-up in the New Approaches to Coronary Intervention (NACI) registry.

Higher complication rates and lower success rates for treatment of women compared with men have been reported in prior studies of coronary angioplasty and in most early reports of outcome with new coronary interventional devices. In multivariate analysis this has been attributed largely to older age and other unfavorable clinical characteristics. These results are reflected in the current guidelines for coronary angioplasty. Women in prior studies have also had different distributions of vessel and lesion characteristics, but the influence of these differences on the outcome of new-device interventions have not been adequately evaluated. This article evaluates the influence of gender on clinical and angiographic characteristics, interventional procedure and complications, angiographic success, and clinical outcomes at hospital discharge and 1-year follow-up, as observed in the New Approaches to Coronary Intervention (NACI) registry. The NACI registry methodology has been reported in detail elsewhere in this supplement. This study focuses on the 90% of patients-975 women and 1,880 men-who had planned procedures with a single new device and also had angiographic core laboratory readings. Women compared with men were older, had more recent onset of coronary ischemic pain that was more severe and unstable, and had more frequent histories of other adverse clinical conditions. The distributions of several but not all angiographic characteristics before intervention were considered more favorable to angioplasty outcome in women. Differences were observed in device use and procedure staging. Angiographically determined average gain in lumen diameter after new-device intervention, with or without balloon angioplasty, was significantly less in women (1.38 mm) than in men (1.53 mm; p < 0.001); this 0.15 mm difference is consistent with the 0.16-mm smaller reference vessel lumen diameter of women. However, final percent diameter stenoses and TIMI flow and lesion compliance characteristics were similar. Among procedural complications, only treatment for hypotension, blood transfusion, and vascular repair occurred more often in women. More women than men were clinically unstable (2.1% vs 1.1%) or went directly to emergent coronary artery bypass graft surgery (CABG; 1.2% vs 0.6%) on leaving the interventional laboratory. However, in-hospital death (1.4% vs 1.1%), Q-wave myocardial infarction (MI) (0.9% vs 1.1%), and emergent CABG (1.5% vs 1.0%, for women and men, respectively) were not significantly different. Nonemergent CABG was more frequent in women (1.8% vs 0.9%; p < 0.05) and length of hospital stay after device intervention was longer (4.4 days vs 3.8 days in men; p < 0.01). In both univariate and multivariate analyses gender did not emerge as a significant variable in relation to the combined endpoint, death, Q-wave MI, or emergent CABG at hospital discharge. At 1-year follow-up more women than men reported improvement in angina (70% vs 62%) and fewer women than men had had repeat revascularization (32% vs 36%). Similar proportions were alive and free of angina, Q-wave MI and repeat revascularization (46% of women vs 45% of men). Although several procedure-related complications were more frequent in women than men after coronary interventions with new devices, no important disadvantages were observed for women in the rates of major clinical events at hospital discharge and at 1-year clinical follow-up. Additional studies are needed to evaluate the complex interplay of clinical, vessel, and lesion characteristics on success and complications of specific interventional techniques and to determine whether gender, per se, is a risk factor and whether gender specific interventional strategies may be beneficial.

Aged↗
PubMed1997

High-speed rotational atherectomy of human coronary stenoses: acute and one-year outcomes from the New Approaches to Coronary Intervention (NACI) registry.

High-speed rotational atherectomy (RA) is a new percutaneous procedure for treatment of coronary stenoses that operates by the unique mechanism of plaque abrasion. This article reports acute (in-hospital) outcomes and 1-year follow-up in a large cohort of patients treated with this device by NACI investigators. A total of 525 patients with 670 lesions treated with RA form the substrate of this report. Patients tended to be older (mean age 64.8 years) than those in previously reported series of percutaneous transluminal coronary angioplasty (PTCA), with more extensive disease and more complex lesions. Calcification was present in 54% of lesions, and eccentricity in 41%. Balloon angioplasty postdilation was performed after RA in 88% of cases. Angiographic and procedural success (angiographic success without death, Q-wave myocardial infarction [MI] or emergency coronary artery bypass graft [CABG] surgery) rates were 89% and 88%, respectively. Acute in-hospital events included 4 deaths (1%) and 1 emergency CABG surgery (0.4%). MI occurred in 6% of patients, consisting predominantly of non-Q-wave MI (5%). After RA, angiographic complications included coronary dissection (12%), abrupt closure (5%), side branch occlusion (3%), and distal embolization (3%). Most of these were resolved after postdilation except for coronary dissection, which was present in 15% of lesions treated. Mean length of stay was 3 days. At 1-year follow-up, 27% of patients required target lesion revascularization and 30% had experienced death, Q-wave MI, or target lesion revascularization. Preprocedural characteristics that independently predicted 1-year death, Q-wave MI, or target lesion revascularization were male gender, high risk for surgery, target lesions that were proximal to or in bifurcations, eccentric, long, or highly stenosed. RA, even when applied to lesions of traditionally unfavorable morphology, appears to provide reasonable procedural and angiographic success rates. Restenosis and progression of disease contribute to subsequent clinical and procedural events.

Aged↗
PubMed1997

Excimer laser coronary angioplasty: the New Approaches to Coronary Intervention (NACI) experience.

In the New Approaches to Coronary Intervention (NACI) registry, 887 patients were electively treated with excimer laser coronary angioplasty (ELCA) for coronary artery disease. The Advanced Interventional System (AIS) system was used in 487 cases; the Spectranetics system, in 400. The mean age was 63.4 years. Most patients had unstable angina (60.3%); 43.7% had a prior myocardial infarction; and 18.6% were high risk or inoperable patients. Mean ejection fraction was 55.4%. A total of 1,000 lesions were treated in the 887 patients. Of the 1,000 lesions treated with ELCA in the 887 patients, 36% were in the right coronary artery; 33%, left anterior descending; 13%, circumflex; 3%, left main; and 16.6%, vein graft. By angiographic core laboratory analysis available for 752 (85%) patients with 839 lesions, lesions were 12.76 mm long. The minimum lumen diameter increased to 1.29 mm after the laser and finally to 1.95 mm after adjunctive percutaneous transluminal coronary angioplasty (PTCA) (which was performed in 93% of all lesions), with a final residual stenosis of 32.1% and Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in 95%. Dissections of grades B, C, or D were seen after 22.0% of initial laser attempts, and postlaser perforations were noted in 2.6%. Additional such dissections accumulated after adjunctive PTCA but the perforation rate remained low. Procedural success was achieved in 84% of patients, but 1.2% died, 0.7% experienced Q-wave myocardial infarction (MI), and 2.7% required emergency bypass surgery. Multiple logistic regression analysis could not identify any independent predictors of these in-hospital complications. One-year mortality was 5.7% and the cumulative incidence of Q-wave MI was 1.5%. Coronary artery bypass graft (CABG) surgery was performed in 15.0% of patients whereas 25.5% required repeat percutaneous intervention with a target lesion revascularization rate of 31%. Independent predictors of death, Q-wave MI, or target lesion revascularization (which, combined, occurred in 35.6% of patients) were the absence of prior MI, ELCA in the circumflex, perforation after the procedure, and small (<2 mm) final minimal lumen diameter. Considering the large number of patients with high-risk lesions, laser angioplasty was performed with excellent procedural success rates and a reasonable incidence of major complications.

Aged↗
PubMed1997

Documentation of decline in morbidity in women undergoing coronary angioplasty (a report from the 1993-94 NHLBI Percutaneous Transluminal Coronary Angioplasty Registry). National Heart, Lung, and Blood Institute.

To determine whether there has been an improvement in the relatively unfavorable outcome of percutaneous transluminal coronary angioplasty (PTCA) in women, the 1993 to 1994 National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry collected data from 12 clinical centers that participated in the earlier registries. We compared 274 consecutive women in 1993 to 1994 with 545 consecutive women in 1985 to 1986 undergoing PTCA. Women in the 1993 to 1994 registry were older (64.3 vs 61.0 years, p <0.001) with more diabetes mellitus (34.3% vs 19.9%, p <0.001), congestive heart failure (13.7% vs 8.6%, p <0.05), and comorbid disease (19.5% vs 9.3%, p <0.001). Left ventricular function and multivessel coronary artery disease were similar between groups. Angiographic success (90.9% vs 85.1%, p <0.05) and clinical success (89.4% vs 79.4%, p <0.001) were higher in women undergoing PTCA in 1993 to 1994 than in 1985 to 1986. Whereas there was no difference in in-hospital mortality (1.5% vs 2.6%), the incidence of nonfatal myocardial infarction (1.8% vs 4.6%, p <0.05), emergency coronary artery bypass graft surgery (1.8% vs 4.6%, p <0.05), and the combined end points of death, myocardial infarction, and emergency coronary artery bypass grafting (4.4% vs 9.7%, p <0.01) were lower in women in 1993 to 1994 than in women in 1985 to 1986, respectively. Multivariate analysis revealed an odds ratio of 0.36 (95% confidence interval 0.18 to 0.72) for major complications and of 2.34 (95% confidence interval, 1.49 to 3.69) for clinical success in the 1993 to 1994 versus 1985 to 1986 registry. Therefore, despite a higher risk profile, women undergoing PTCA in 1993 to 1994 have a higher clinical success and lower major complication rate than women treated with PTCA in 1985 to 1986.

Aged↗
PubMed1996

A comparison of debulking versus dilatation of bifurcation coronary arterial narrowings (from the CAVEAT I Trial). Coronary Angioplasty Versus Excisional Atherectomy Trial-I.

We compared the effectiveness of percutaneous transluminal coronary angioplasty and directional coronary atherectomy for the management of bifurcation coronary lesions in 1,012 patients enrolled in the Coronary Angioplasty Versus Excisional Atherectomy Trial-I. Directional coronary atherectomy was associated with less angiographic residual stenosis, but with a higher rate of side-branch closure and non-Q-wave myocardial infarction.

Aged↗
PubMed1995

Prospective case-control comparison of percutaneous transluminal coronary revascularization in patients with multivessel disease treated in 1986-1987 versus 1991: improved in-hospital and 12-month results. Multivessel Angioplasty Prognosis Study (MAPS) Group.

OBJECTIVES: This study sought to ascertain whether early and 12-month clinical outcomes after percutaneous coronary revascularization have improved between 1986-1987 and 1991. BACKGROUND: Since the mid-1980s, when the results of percutaneous revascularization were considered to be somewhat static, justifying large-scale clinical trials of percutaneous transluminal coronary angioplasty versus other modes of therapy, balloon technology has improved, and several new percutaneous revascularization techniques have become available. The clinical results of the current integrated approach to revascularization compared with those for coronary angioplasty alone in the late 1980s are not known. METHODS: In this prospective case-control study, 200 consecutively treated patients with multivessel disease in 1991 were studied prospectively and compared with 400 consecutive patients from the same centers during 1986-1987. Patients from 1991 were matched with earlier patients on the basis of four previously described prognostic determinants (left ventricular ejection fraction, presence of unstable angina, diabetes and target lesion morphology score) and the treating institution and were assessed for treatment outcome (completeness of revascularization, procedural success and event-free survival [freedom from death, myocardial infarction and further revascularization]). RESULTS: The 1991 cohort of patients was older (mean [+/- SD] age 62 +/- 11 vs. 58 +/- 11 years, p < 0.001) and tended to have slightly worse left ventricular function (ejection fraction 56 +/- 10% vs. 58 +/- 11%, p = 0.009) than the 1986-1987 cohort. Overall lesion morphology risk scores were similar. New devices (other than coronary angioplasty) were used in 26% of patients. The 1991 patient cohort had more frequent total revascularization (35% vs. 21%, p = 0.003), fewer emergency bypass operations (1.0% vs. 5.5%, p = 0.006) and an improved overall procedural success rate (90% vs. 84%, p = 0.04). In addition, at 12 months the event-free survival rate was superior in the 1991 cohort (73.3% vs. 63.6%, p = 0.02), although there was no difference in infarct-free survival rate (94.6% vs. 93.2%, p = NS). CONCLUSIONS: Improved results with percutaneous revascularization in 1991 have important implications for patient care and interpretation of ongoing randomized trials enrolling patients in the late 1980s and intending to compare standard coronary angioplasty with other forms of therapy.

Angioplasty, Balloon, Coronary↗
PubMed1995

High speed rotational atherectomy: outcome in calcified and noncalcified coronary artery lesions.

OBJECTIVES: This study sought to determine the success and complication rates of high speed rotational coronary atherectomy in calcified and noncalcified lesions. BACKGROUND: Percutaneous transluminal coronary angioplasty and directional coronary atherectomy of calcified lesions are associated with reduced procedural success and increased complications. Rotational atherectomy using the Rotablator catheter abrades noncompliant plaque and may improve outcome in calcified lesions. METHODS: Data from the completed Multicenter Rotablator Registry of 2,161 rotational atherectomy procedures in single lesions were analyzed to determine the relative efficacy of rotational atherectomy for 1,078 calcified and 1,083 noncalcified lesions. The power of the study was 0.86 to detect a significant difference in outcome, if the true success rates in the noncalcified and calcified lesions were 96% and 93%, respectively. RESULTS: Patients with calcified lesions were older (mean [+/- SD] age 66.2 +/- 10.3 vs. 60.5 +/- 11.0 years, p = 0.0001) than those with noncalcified lesions. Calcified lesions were more frequently new (75% vs. 64%, p = 0.0001), angulated (27% vs. 22%, p = 0.02), eccentric (75% vs. 64%, p = 0.0001) and long (32% vs. 27%, > 10 mm in length, p = 0.01). They were also more often complex (57% vs. 46%, p = 0.001) and located in the left anterior descending coronary artery (51% vs. 44%, p = 0.001). Adjunctive coronary angioplasty was used in 82.9% of calcified and 66.9% of noncalcified lesions. Procedural success, defined as < 50% residual stenosis without major complications, was achieved in 94.3% of calcified and 95.2% of noncalcified lesions (p = 0.32). Major complication rates were 4.1% in calcified and 3.1% in noncalcified lesions (p = 0.24). Non-Q wave myocardial infarction was documented in 10.0% of calcified and 7.7% of noncalcified lesions (p = 0.054). Mean postprocedural residual stenosis was 21.6 +/- 13.9% in calcified and 23.3 +/- 15% in noncalcified lesions (p = 0.39). CONCLUSIONS: In this review of data from a large multicenter registry, the success rate of rotational atherectomy was not reduced by calcification despite the more frequent complex nature of the calcified lesions. The Rotablator catheter is likely to be the device of choice for percutaneous intervention in calcified lesions, but definitive conclusions await the results of randomized trials.

Aged↗
PubMed1994

Immediate results of interventional devices for coronary ostial narrowing with angina pectoris.

Angioplasty of aorto-ostial lesions has had suboptimal results. This study reports on the immediate results of new debulking devices (atherectomy, excimer laser) in the treatment of aorto-ostial disease. Thirty-one vessels (29 patients) with an ostial lesion treated with a new device (group I) were compared with 15 vessels (13 patients) with an ostial lesion treated with angioplasty alone during the preceding 24 months (group II). Both groups were similar in their clinical characteristics. A larger proportion of vessels in group I (64%) compared with group II (7%) had unfavorable features for angioplasty. Procedural success was similar: 28 vessels in group I (91%) and 14 in group II (93%). Among the new devices, success was also similar: atherectomy in 8 arteries (89%), rotablator in 4 (100%) and excimer laser in 17 (94%). The acute gain was more significant with new devices: absolute reduction in percent stenosis was 66% for directional atherectomy, 67% for rotational atherectomy (p = 0.016 compared with angioplasty), 52% for excimer laser (p = 0.09) and 46% for angioplasty. In group I, 2 patients (6%) required emergency bypass surgery during our early experience; no deaths or Q-wave myocardial infarctions occurred. Group II had no complications. Therefore in aorto-ostial lesions, despite a much higher prevalence of unfavorable angiographic characteristics, new devices had (1) a success rate of > or = 90%, (2) a significantly larger acute gain compared with angioplasty alone, and (3) an acceptable complication rate. Larger studies with complete angiographic follow-up are needed to assess restenosis.

Aged↗
PubMed1994

Histopathologic correlates of unstable ischemic syndromes in patients undergoing directional coronary atherectomy: in vivo evidence of thrombosis, ulceration, and inflammation.

Complex coronary morphologic abnormalities with thrombus and ulceration have been recognized in acute ischemic syndromes by angiography, angioscopy, and autopsy. However, in vivo histopathologic correlates of unstable ischemic syndromes have not been described. The purpose of this study was to characterize intracoronary lesion morphologic abnormalities by analyzing specimens excised by directional atherectomy in patients with different ischemic syndromes. Tissue specimens removed by directional coronary atherectomy of primary lesions in native vessels were matched blindly to the clinical status of 130 patients representing 43% of a consecutive directional coronary atherectomy population of 300 patients; 824 specimens (range per patient 1 to 30, mean 6.3) were obtained. Clinical subgroups were prospectively classified as recent myocardial infarction (< or = 15 days, mean 6, range 1 to 15 days), 48 patients; prolonged rest angina, 34 patients; crescendo angina, 29 patients; and stable angina, 19 patients. Shavings were prospectively analyzed for presence of thrombus, ulceration, or chronic inflammatory cells. Thrombus was observed in 33 (69%) patients with recent myocardial infarction, 17 (50%) with rest angina, 12 (41%) with crescendo angina, 7 (37%) with stable angina (p = 0.048). Plaque ulceration was identified in 12 (25%) patients with recent myocardial infarction, 4 (12%) with rest angina, 2 (7%) with crescendo angina, and 1 (5%) with stable angina (p = 0.09). Inflammatory cells were noted in the specimens of 32 (67%) patients with recent myocardial infarction, 16 (45%) with rest angina, 12 (41%) with crescendo angina, and 9 (45%) with stable angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗