Gregory S. Pavlides

Clinical and angiographic results of transluminal extraction coronary atherectomy in saphenous vein bypass grafts.

BACKGROUNDnTransluminal extraction coronary (TEC) atherectomy is a relatively new device that has recently been approved by the Food and Drug Administration. Because of its ability to aspirate clot and atheromatous material, TEC atherectomy may be useful in patients with stenoses in saphenous vein bypass grafts.nnnMETHODS AND RESULTSnTEC atherectomy was performed on 158 saphenous vein graft lesions in 146 consecutive patients with a mean age of 65 +/- 8 years (78% men). Clinical indications for atherectomy included stable angina (37%), unstable angina (54%), and postinfarction angina after recent (< 1 month) myocardial infarction (8%). Patients with acute myocardial infarction and target vessels < 2 mm in diameter were excluded. The mean age of the bypass graft was 8.3 +/- 3.0 years, and 17% were diffusely diseased and degenerated. Complex lesion morphology included total occlusion (6%), eccentricity (64%), ulceration (18%), and thrombus (28%). The TEC atherectomy cutter was successfully advanced through 144 lesions (91%), but technical failures occurred in 14 lesions (9%), and these were subsequently managed by successful balloon angioplasty. Quantitative angiography revealed an increase in lumen diameter from 0.9 +/- 0.5 mm, to 1.5 +/- 0.7 mm after TEC atherectomy, to 2.3 +/- 0.8 mm after percutaneous transluminal coronary angioplasty (PTCA) (P < .001), which corresponded to decreases in diameter stenosis from 75 +/- 14%, to 58 +/- 20% after TEC atherectomy, to 36 +/- 22% after PTCA (P < .001). Device success was achieved in 39.2% (post-TEC atherectomy decrease in diameter stenosis > or = 20%), and procedural success was achieved in 84% (final diameter stenosis < 50% in the absence of a major complication). Angiographic complications were evident in 33 lesions (20.7%) immediately after TEC atherectomy and in 8 lesions (5%) after PTCA, including distal embolization (11.9%), no-reflow (8.8%), and abrupt closure (5.0%), but no perforations. Adjunctive PTCA (and other medical therapy) successfully managed 61% of angiographic complications. Serious clinical complications included in-hospital death in 3 patients (2.0%), emergency bypass surgery in 1 patient who died (0.7%), Q wave myocardial infarction in 3 patients (2.0%), non-Q wave myocardial infarction in 4 patients (2.7%), vascular injury requiring surgical repair and/or blood transfusion in 9 patients (6.1%), and hemorrhagic cerebral infarction in 4 patients (2.7%). Using a composite clinical end point defined as in-hospital death, emergency bypass surgery, or myocardial infarction, the strongest independent correlate (P < .001) of a severe clinical complication was the development of one or more serious angiographic complications (no-reflow, distal embolization, or abrupt closure) immediately after TEC atherectomy. Complete clinical follow-up was available in 118 (92%) of 128 eligible patients at an interval of 6.0 +/- 2.5 months after discharge. Late cardiac outcome included recurrent angina treated with medical therapy (18%), repeat percutaneous intervention on the original target lesion (26%), repeat coronary artery bypass surgery (5%), Q wave myocardial infarction (4%), and late cardiac death (7%). Angiographic follow-up in 105 (80%) of 132 eligible lesions revealed a restenosis rate of 69% (defined as a diameter stenosis > 50%), including 30 lesions (29%) with total occlusion of the original lesion.nnnCONCLUSIONSnIn patients with stenoses in saphenous vein bypass grafts, TEC atherectomy is limited by the frequent need for adjunctive balloon angioplasty to achieve adequate lumen enlargement and to manage TEC atherectomy-induced complications. Although the incidence of serious clinical complications is similar to that of other percutaneous interventions in vein grafts, there is a high incidence of restenosis and late vessel occlusion. Prospective randomized studies are needed to determine the best revascularization strategy for high-risk patients with old degenerated vein

Predictors of long-term event-free survival after percutaneous balloon mitral valvuloplasty

Previous studies have shown that long-term event-free survival after percutaneous balloon mitral valvuloplasty (PBMV) could be predicted by several baseline characteristics. However, the extent of the predictive variables has not been defined accurately yet. In this study, 40 baseline demographic, clinical, echocardiographic, and hemodynamic variables of 128 consecutive patients with mitral stenosis who underwent PBMV in a single institution, were analyzed in order to predict long-term event-free survival, defined as absence of death, mitral valve replacement, or repeat PBMV. Univariate survival analysis showed that age (p = 0.03), history of commissurotomy or mitral valvuloplasty (p = 0.05), calcium grade (p = 0.008), echo score (p = 0.0001), preprocedure cardiac output (p = 0.03), preprocedure valve area (p = 0.0007), postprocedure mean left atrial pressure (p = 0.0001), postprocedure valve area (p = 0.0001), postprocedure valve gradient (p = 0.013), and postprocedural mitral regurgitation (p = 0.01) were statistically significant predictors of event-free survival. Additionally, the absolute and/or relative procedural change of the following variables were found to be statistically significant predictors of event-free survival: left atrial pressure (p = 0.01), valve area (p = 0.0001), and valve gradient (p = 0.02). Multivariate Cox proportional hazard analysis indicated that when only variables available before the procedure were considered, echo score (p = 0.002) and preprocedure valve area (p = 0.0002) were found to be independent predictors of event-free survival. When both pre- and postprocedure variables were considered, echo score (p = 0.002) and postprocedure valve area (p = 0.0001) were found to be independent predictors of event-free survival. In conclusion, mitral valve morphology reflected by echo score, and baseline and postprocedure mitral valve area were found to be the strongest independent predictors of event-free survival after PBMV.

Contribution of transesophageal echocardiography to patient diagnosis and treatment: A prospective analysis

The capability of transesophageal (TEE) versus transthoracic (TTE) echocardiography as a diagnostic tool in clinical practice was prospectively examined in 86 consecutive cases. A conclusive diagnosis was possible in 95% with TEE, whereas the same result was achieved in 48% by TTE. Specifically, TEE provided a conclusive diagnosis in 14 of 16 cases of infective endocarditis, while TTE gave this result in 4 of the 16 cases (p less than 0.001). Similarly, TEE allowed a conclusive diagnosis in 11 of 11 instances of aortic dissection, while TTE gave this indication in two cases (p less than 0.001). TEE was similarly effective in eight of eight cases of atrial thrombi, whereas TTE gave the diagnosis in three of eight cases (p less than 0.01). In five subjects with intracardiac masses, TEE gave a conclusive diagnosis in all five, whereas TTE was able to diagnose conclusively in one subject (p less than 0.02). In seven patients with mitral regurgitation, TEE gave the conclusive diagnosis in all seven and TTE was able to provide this information in four (p = NS). TEE was able to provide a conclusive diagnosis in four patients with aortic insufficiency, and TTE gave the same information in two of the four (p = NS). In 14 patients with prosthetic valve dysfunction, TEE gave the diagnosis in 12 and TTE gave it in eight patients (p = NS). Both methods gave a conclusive diagnosis in 13 out of 13 cases of mitral stenosis (p = NS). Also, TEE provided a conclusive diagnosis in eight of eight patients with adult congenital heart disease and TTE gave this information in four (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Safety and efficacy of urokinase during elective coronary angioplasty

Eighty-nine of 462 patients were treated with adjunctive urokinase during elective percutaneous transluminal coronary angioplasty (PTCA), 26% for unstable angina, 34% for intracoronary thrombus, 27% for intimal dissection, 10% for abrupt closure, and 3% for saphenous vein graft embolism. The 80 patients treated before abrupt closure (group A) were compared with 167 patients with similar profiles who did not receive urokinase (group B). Procedural success rates were similar. Adverse cardiac events (abrupt closure, myocardial infarction, emergency coronary artery bypass, or death) in group A versus group B occurred in: 1 of 30 (3%) versus 5 of 27 (18.5%) (p = 0.07) with intracoronary thrombus, 5 of 45 (9%) versus 18 of 110 (16.3%) with unstable angina, 1 of 12 (8%) versus 4 of 13 (31%) with unstable angina with intracoronary thrombus, 4 of 33 (12%) versus 14 of 97 (14.4%) with unstable angina without intracoronary thrombus, and 5 of 24 (20.8%) versus 6 of 66 (9%) with intimal dissection. Hemorrhagic complications occurred in 11% of patients who were treated with urokinase versus 9% of patients who were not (p = NS). No difference in blood transfusions existed. Thus urokinase was found to be safe during elective PTCA. In patients with intracoronary thrombus, urokinase appears to decrease the incidence of new adverse cardiac events, whereas in patients with intimal dissection it might have an adverse effect.

Effect of peripheral cardiopulmonary bypass on left ventricular size, afterload and myocardial function during elective supported coronary angioplasty

Although cardiopulmonary bypass support has been increasingly used for high risk coronary angioplasty, few data exist regarding its effects on left ventricular function. Accordingly, in 20 patients changes in left ventricular size, afterload and myocardial function were assessed by continuous hemodynamic monitoring and simultaneous two-dimensional echocardiography during cardiopulmonary bypass-supported high risk angioplasty. The cross-sectional left ventricular area during bypass support remained unchanged during diastole, whereas during systole it decreased (from 29.6 +/- 11.4 to 27.6 +/- 10.4 cm2, p less than 0.05). Global left ventricular function expressed as fractional area change remained unchanged from baseline to bypass support but decreased during balloon inflation (from 0.27 +/- 0.11 to 0.17 +/- 0.09, p less than 0.001). The end-systolic meridional wall stress decreased during bypass support (from 141 +/- 75 to 110 +/- 58 x 10(3) dynes/cm2, p less than 0.02). Regional myocardial function was assessed by a wall motion score (0 = normal, 1 = hypokinesia, 2 = akinesia and 3 = dyskinesia). Regions supplied by a stenotic (greater than or equal to 50% diameter) vessel deteriorated during bypass support (score from 0.9 +/- 0.8 to 1.06 +/- 0.8, p less than 0.01), whereas regions supplied by a nonstenotic vessel did not. Regions supplied by the target vessel deteriorated further during balloon inflation (score from 0.7 +/- 0.6 to 1.7 +/- 0.75, p less than 0.001). Thus, although left ventricular size and global function remain unchanged and afterload decreases during bypass support, myocardial dysfunction in regions supplied by a stenotic vessel may occur. Furthermore, regional and global left ventricular dysfunction still occur with angioplasty balloon inflation during cardiopulmonary bypass support.

Detailed clinical and angiographic analysis of transluminal extraction coronary atherectomy for complex lesions in native coronary arteries

OBJECTIVESnThe purpose of this study was to describe the results of transluminal extraction coronary atherectomy in native coronary arteries.nnnBACKGROUNDnTransluminal extraction coronary atherectomy was approved by the Food and Drug Administration for use in native coronary arteries and vein grafts.nnnMETHODSnBetween December 1988 and July 1992, transluminal extraction coronary atherectomy was performed in 181 native coronary arteries in 175 patients. A detailed angiographic and clinical assessment was performed.nnnRESULTSnQuantitative angiography (mean +/- SD) revealed an increase in minimal lumen diameter from 1.0 +/- 0.6 mm before to 1.3 +/- 0.7 mm after atherectomy, to 2.1 +/- 0.8 mm after final treatment (p < 0.001), corresponding to a diameter stenosis of 70 +/- 16%, 61 +/- 21% and 36 +/- 21%, respectively (p < 0.001). Final procedural success (final diameter stenosis < 50%, no major complications) was achieved in 84%. Adjunctive angioplasty was used after atherectomy in 152 lesions (84%) to further enlarge lumen dimensions (130 lesions, 72%), salvage technical failures (2 lesions, 1%) and reverse atherectomy-induced abrupt closures (20 lesions, 11%). Clinical complications included death (2.3%), Q wave myocardial infarction (3.4%) and emergency bypass surgery (2.8%). The strongest independent correlate of major clinical complications was development of abrupt closure immediately after atherectomy (p = 0.01). Clinical follow-up of 92% of eligible patients revealed clinical restenosis (repeat intervention, late bypass surgery, myocardial infarction or death) in 28.5%. Angiographic follow-up of 83% of eligible lesions revealed a restenosis rate (diameter stenosis > 50%) of 61%.nnnCONCLUSIONSnTransluminal extraction coronary atherectomy is limited by a modest degree of lumen enlargement, frequent need for adjunctive angioplasty and a high restenosis rate. For complex lesions in native coronary arteries, transluminal extraction coronary atherectomy appears to offer no advantage over conventional balloon angioplasty.

Hemodynamic and metabolic effects of venoarterial cardiopulmonary support in coronary artery disease

Coronary angioplasty was performed on 14 high-risk patients supported with venoarterial partial cardiopulmonary bypass. Hemodynamic, metabolic and physiologic parameters were monitored to assess the effect of cardiopulmonary support in conscious patients. Cardiopulmonary support caused a decrease in systolic (45 +/- 17 to 27 +/- 14 mm Hg, p less than 0.001), diastolic (23 +/- 12 to 14 +/- 8 mm Hg, p less than 0.005) and mean (29.7 +/- 13.2 to 18 +/- 9 mm Hg, p less than 0.001) pulmonary artery pressures. Aortic systolic (129 +/- 18 to 106 +/- 17 mm Hg, p less than 0.001), mean (89 +/- 19 to 84 +/- 19 mm Hg, p less than 0.05) and pulse (64 +/- 17 to 37 +/- 16 mm Hg, p less than 0.00001) pressures also decreased. Heart rate and aortic diastolic pressures were unchanged. End-systolic wall stress (122 +/- 48 x 10(3) to 96 +/- 44 x 10(3) dynes/cm2, p less than 0.001) and left ventricular end-diastolic diameter (5.7 +/- 0.8 to 5.5 +/- 0.9 cm, p less than 0.05) were reduced during partial cardiopulmonary bypass. After initiation of cardiopulmonary support, normal lactate extraction across the coronary circulation was diminished or converted to lactate production (38 +/- 23 to 2 +/- 29%, p less than 0.005). There was a marked reduction in hematocrit (41 +/- 4 to 28 +/- 5%, p less than 0.0001) and platelet count (259,000 +/- 57,600/ml to 145,900 +/- 46,000/ml, p less than 0.0001) after bypass. Cardiopulmonary bypass successfully supported all patients during balloon inflation, for an optimal angioplasty result.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical, Hemodynamic, Electrocardiographic and Mechanical Events During Nonocclusive, Coronary Atherectomy and Comparison with Balloon Angioplasty

The periprocedural events and myocardial function during nonocclusive coronary atherectomy by Rotablator or transluminal extraction catheter (TEC) may differ from events during balloon angioplasty. This may have important clinical consequences and needs to be defined further. Therefore, 17 patients undergoing Rotablator and 18 undergoing TEC atherectomy were assessed by clinical, hemodynamic and electrocardiographic monitoring and simultaneous transesophageal echocardiography. The findings were compared with similar parameters during subsequent balloon angioplasty performed in 16 of 17 patients undergoing Rotablator and 14 of 18 undergoing TEC atherectomy. Chest pain occurred more frequently during balloon inflation than during either atherectomy (p less than 0.02), whereas ST-segment and T-wave electrocardiographic changes were equally frequent. Transient second- or third-degree atrioventricular block occurred in 6 patients during Rotablator but in none during TEC atherectomy or balloon inflation (p less than 0.01 for each). Hemodynamic parameters and global left ventricular function remained unchanged during atherectomy. Regional myocardial function in the distribution of the target coronary artery, assessed by a wall motion score, was not affected during Rotablator, but deteriorated slightly during TEC atherectomy and more significantly during balloon inflation (score from 0.3 +/- 0.5 to 1.0 +/- 0.7 during TEC and 2.0 +/- 0.6 during balloon inflation, p less than 0.005 for both). Thus, chest pain is infrequent, whereas hemodynamics and global left ventricular function are preserved during Rotablator and TEC atherectomy. Transient atrioventricular block during Rotablator and regional myocardial dysfunction during TEC atherectomy may occur without significant consequences. These data suggest that these techniques may be preferable to balloon angioplasty for preserving intraprocedural left ventricular function.

Usefulness of percutaneous transluminal coronary angioplasty after new device coronary interventions

Percutaneous transluminal coronary angioplasty (PTCA) is often required immediately after laser and atherectomy devices to enlarge lumen dimensions and to salvage device failures. Between January 1989 and June 1992, adjunctive PTCA was applied to 83% of narrowings treated with new interventional devices, including 85% of transluminal extraction atherectomy (n = 290), 72% of high-speed mechanical rotational atherectomy (n = 79), and 89% of excimer laser angioplasty (n = 118) lesions (p = NS). Device success was defined as a decrease in diameter stenosis > or = 20%; procedural success was defined as a final diameter stenosis < or = 50% after PTCA; and salvage PTCA was defined as use of PTCA to manage device-induced vessel occlusion. Although adjunctive PTCA was applied to 487 lesions, it was used to further enlarge the lumen after initial device success in 139 lesions (28.5%). In contrast, adjunctive PTCA was used after initial device failure in 348 lesions (71.5%), including after minimal or no change (decrease in diameter stenosis by 0 to 19%) in diameter stenosis in 244 lesions (50%) and after worsening of diameter stenosis in 104 lesions (21.5%). Salvage PTCA after device-induced vessel occlusion was performed in 61 lesions (12.6%). However, final procedural success after PTCA was achieved in 412 lesions (85%), with a low incidence of Q-wave myocardial infarction (3.5%), emergency bypass surgery (1.8%) and death (2.3%).

Value of transesophageal echocardiography during complex or high-risk coronary interventions in the cardiac catheterization laboratory

The increasing complexity of coronary intervention and the limitations of hemodynamic and electrocardiographic monitoring have facilitated the introduction of new imaging techniques in the cardiac catheterization laboratory. Transesophageal echocardiography (TEE) has proved valuable for left ventricular (LV) monitoring during high-risk surgery, but its reported use in the cardiac catheterization laboratory has been limited. Accordingly, we assessed the feasibility and value of TEE during complex or high-risk coronary intervention in the catheterization laboratory. The TEE probe was successfully introduced in 53 of 54 (98%) attempted cases. The primary imaging goals were LV monitoring in 39 (74%), left main coronary artery (LMCA) imaging in 9 (17%) and both in 5 (9%) cases. LV monitoring was successful in 43 of the 44 (98%) attempted cases. In 25 (58%) of these, additional important observations were made by TEE that were not apparent by symptoms, or hemodynamic, electrocardiographic or radiographic monitoring. These included unexpected changes in regional myocardial function (n = 20), alteration in LV size (n = 2), exclusion of considered pericardial tamponade (n = 2) and detection of unsuspected mitral regurgitation (n = 1). Management of the interventional procedure was directly influenced by the findings of TEE in 11 of the 43 (26%) monitored cases. The LMCA was successfully visualized in 13 of the 14 (93%) attempted cases. In 11 of these, measurement of the stenotic lesion diameter by TEE correlated well with quantitative angiography both before (r = 0.83, standard error of the estimate = 0.01, p less than 0.002) and after (r = 0.80, standard error of the estimate = 0.03, p less than 0.005) intervention.(ABSTRACT TRUNCATED AT 250 WORDS)