The impact of statistical adjustment on economic profiles of interventional cardiologists.

OBJECTIVES: The objective of this study was to identify preprocedure patient factors associated with percutaneous intervention costs and to examine the impact of these patient factors on economic profiles of interventional cardiologists. BACKGROUND: There is increasing demand for information about comparative resource use patterns of interventional cardiologists. Economic provider profiles, however, often fail to account for patient characteristics. METHODS: Data were obtained from Duke Medical Center cost and clinical information systems for 1,949 procedures performed by 13 providers between July 1, 1997, and December 31, 1998. Patient factors that influenced cost were identified using multiple regression analysis. After assessing interprovider variation in unadjusted cost, mixed linear models were used to examine how much cost variability was associated with the provider when patient characteristics were taken into account. RESULTS: Total hospital costs averaged $15,643 (median, $13,809), $6,515 of which represented catheterization laboratory costs. Disease severity, acuity, comorbid illness and lesion type influenced total costs (R(2) = 38%), whereas catheterization costs were affected by lesion type and acuity (R(2) = 32%). Patient characteristics varied significantly among providers. Unadjusted total costs were weakly associated with provider, and this association disappeared after accounting for patient factors. The provider influence on catheterization costs persisted after adjusting for patient characteristics. Furthermore, the pattern of variation changed: the adjusted analysis identified three new outliers, and two providers lost their outlier status. Only one provider was consistently identified as an outlier in the unadjusted and adjusted analyses. CONCLUSIONS: Economic profiles of interventional cardiologists may be misleading if they do not adequately adjust for patient characteristics before procedure.

Provisional stenting strategies: systematic overview and implications for clinical decision-making.

Coronary stents reduce the rates of abrupt closure, emergency coronary artery bypass graft surgery and restenosis, but do not prevent myocardial infarction or death at six months. The financial burden of increased stent use and the difficulty in managing in-stent restenosis have provided the impetus to develop provisional stenting strategies. Patients at low risk for restenosis after balloon angioplasty may not derive additional benefit from stent implantation and may be successfully managed with percutaneous transluminal coronary angioplasty (PTCA) alone. Numerous patient, lesion and procedural predictors of restenosis have been identified. Postprocedural assessment using quantitative coronary angiography, intravascular ultrasound (IVUS), coronary flow velocity reserve (CVR) or fractional flow reserve (FFR) may further enhance the ability to predict adverse outcomes after PTCA. Several studies have been performed to investigate the feasibility of provisional stenting strategies using various modalities to identify low risk patients who could be managed with PTCA alone. An optimal or "stent-like" angiographic result after PTCA is associated with favorable clinical outcomes. Preliminary results of studies using IVUS or CVR to guide provisional stenting appear promising. Angiography alone may be inadequate to identify truly low risk patients and may need to be combined with clinical factors, assessment of recoil, IVUS or physiologic indexes. Strategies that avoid unnecessary stenting in even a small proportion of patients may have large impacts on health care costs. Provisional stenting may potentially reduce costs and rates of in-stent restenosis without compromising the quality of health care delivery.

Achieving optimal results with standard balloon angioplasty: can baseline and angiographic variables predict stent-like outcomes?

OBJECTIVES: To predict which patients might not require stent implantation, we identified clinical and angiographic characteristics associated with repeat revascularization after standard balloon angioplasty. BACKGROUND: Stents reduce the risk of repeat revascularization but are costly and may lead to in-stent restenosis, which remains difficult to treat. Identification of patients at low risk for repeat revascularization may allow clinicians to reserve stents for patients most likely to benefit. METHODS: Data from five interventional trials (5,146 patients) were pooled for analysis. We identified patients with optimal angiographic results (final diameter stenosis < or =30% and no dissection) after balloon angioplasty and determined the multivariable predictors of repeat revascularization. RESULTS: Optimal angiographic results were achieved in 18% of patients after angioplasty. The repeat revascularization rate at six months was lower for patients with optimal results (20% vs. 26%, p < 0.001) but still higher than observed in stent trials. Independent predictors of repeat revascularization were female gender (odds ratio [OR] 1.67, p = 0.01), lesion length > or =10 mm (OR 1.62, p = 0.03) and proximal left anterior descending coronary artery lesions (OR 1.62, p = 0.03). For the 8% of patients with optimal angiographic results and none of these risk factors, the repeat revascularization and target vessel revascularization rates were 14% and 8% respectively, similar to rates after stent implantation. Cost analysis estimated that $78 million per year might be saved in the U.S. with a provisional stenting strategy using these criteria compared with elective stenting. CONCLUSIONS: A combination of baseline characteristics and angiographic results can be used to identify a small group of patients at very low risk for repeat revascularization after balloon angioplasty. Provisional stenting for these low risk patients could substantially reduce costs without compromising clinical outcomes.

Percutaneous revascularization of chronic coronary occlusions: an overview.

Patients with a chronic coronary occlusion often undergo coronary angiography after weeks to months of occlusion. The published reports underestimate the extent of this problem because such patients are often arbitrarily assigned to receive medical therapy or undergo bypass surgery as a result of poor success with percutaneous revascularization and substantial restenosis. Thus, there is controversy about the role of angioplasty in this patient cohort. The goal of this overview was to evaluate the available information about angioplasty in chronic coronary occlusions. The primary indication for attempted recanalization of a chronic coronary occlusion has been symptomatic angina pectoris. Anginal status often improves after successful procedures (70% vs. 31% with a failed procedure); left ventricular function may improve; and subsequent referral for coronary artery bypass graft surgery is uncommon (3% vs. 28% in unsuccessful cases). Successful recanalization is achieved in approximately 65% of attempted procedures. Inability to cross the stenosis with a guide wire is the most common cause of procedural failure. Statistically significant predictors of procedural success include older occlusions (75% < 3 months old vs. 37% > or = 3 months old), absence of any anterograde flow through the occlusion (76% with vs. 58% without), angiographically abrupt-appearing occlusions (50% vs. 77% with tapered occlusions), presence of bridging collateral vessels (23% with vs. 71% without) and lesions > 15 mm. Procedural complications occur at a slightly lower incidence than in angioplasty of high grade subtotal stenoses. Long-term success is limited, and restenosis can be expected in > 50% of the patients. The experience with chronic total occlusions of saphenous vein bypass grafts is small, but there appear to be limited procedural success and significant procedural complications, particularly associated with distal emboli. The role of new pharmacologic agents has yet to be defined and that of new devices has been disappointing so far, but further technologic advances are on the horizon.

Diagnostic and prognostic significance of exercise-induced premature ventricular complexes in men and women: a four year follow-up.

Two hundred eighty patients (197 men and 83 women) with normal rest electrocardiograms and no history of prior myocardial infarction were referred for evaluation of chest pain. It was found that exercise-induced premature ventricular complexes had a lower sensitivity, specificity, positive predictive value and negative predictive value in predicting significant coronary artery disease than exercise-induced ST segment depression greater than or equal to 1 mm. The incidence of exercise-induced premature ventricular complexes was not significantly different in patients with no significant coronary artery disease, single vessel disease or multivessel disease. The site of origin of exercise-induced premature ventricular complexes was not helpful in predicting the presence or severity of coronary artery disease. At a mean follow-up period of 47.1 months, exercise-induced premature ventricular complexes did not predict coronary events (cardiac death or nonfatal myocardial infarction) in men or women.

Prospective analysis of possible myocardial damage or hemolysis occurring as a result of prolonged autoperfusion angioplasty in humans.

OBJECTIVES: The purpose of this study was to further explore the procedural safety of prolonged (15-min) dilation using an autoperfusion coronary angioplasty balloon by assessing the degree of myocardial damage or hemolysis, if any, occurring as a result of the procedure. BACKGROUND: Prolonged balloon inflation periods may be beneficial during percutaneous transluminal coronary angioplasty. The duration of standard balloon angioplasty is often limited by the occurrence of myocardial ischemia due to loss of anterograde blood flow. Autoperfusion angioplasty allows continued myocardial perfusion during balloon inflation and has previously been shown to reduce but not totally eliminate acute myocardial ischemia during prolonged (up to 15 min) balloon inflation. The risk of intravascular hemolysis as a result of autoperfusion angioplasty has not yet been fully delineated. METHODS: Sixty-two consecutive patients (76% men; mean age 58 years) undergoing elective percutaneous transluminal coronary angioplasty of a single lesion were studied. Serial electrocardiographic and creatine kinase MB isoenzyme data were examined to detect evidence of myocardial damage. Tests for hemolysis (plasma free hemoglobin, serum haptoglobin and serum lactate dehydrogenase) were obtained in the 1st 24 consecutive patients. RESULTS: Inflation time was 14 +/- 4 min (mean +/- SD) and the procedure was successful (less than or equal to 50% residual lesion stenosis) in 59 patients (95%). Electrocardiographic evidence of myocardial infarction (greater than 1 mm persistent ST segment depression, greater than 1 mm ST segment elevation or new Q waves) was not observed in any patient. Cardiac enzyme assays were within the normal range in all patients. No evidence of hemolysis was found in the 24 consecutive patients studied. CONCLUSIONS: We conclude that prolonged autoperfusion angioplasty can be performed in patients without clinical evidence of myocardial damage or hemolysis.

Effect of buspirone on withdrawal symptoms associated with smoking cessation.

BACKGROUND: Preliminary information suggests that buspirone hydrochloride ameliorates symptoms of nicotine withdrawal. In a double-blind, randomized, placebo-controlled trial, we determined the effects of buspirone on the withdrawal symptoms associated with smoking cessation in 40 long-term cigarette smokers. METHODS: Subjects were randomized to 4 weeks of treatment with either buspirone (n = 20) or placebo (n = 20). Subjects were instructed to maintain their usual cigarette intake during the first 21 days of treatment and to cease smoking on day 22 of treatment. Withdrawal symptoms were subjectively rated before and during smoking cessation. RESULTS: Before smoking cessation, there were no significant differences in the intensity of any withdrawal symptom between the buspirone- and placebo-treated subjects, with the exception of a significantly higher rating for drowsiness in the buspirone group. During the smoking cessation period, the ratings for craving, anxiety, irritability, restlessness, and sadness were significantly lower in the buspirone group than the placebo group. There were no significant differences between the groups in their ratings for hunger, inability to concentrate, or drowsiness. Fifteen buspirone-treated subjects and nine placebo-treated subjects were able to abstain from cigarettes during the entire 7-day smoking cessation period. No subject dropped out of the study for perceived drug side effects. Eight buspirone-treated subjects and five placebo-treated subjects reported side effects, all of which were mild. CONCLUSIONS: Buspirone ameliorated most of the short-term withdrawal symptoms associated with smoking cessation. Further controlled studies will be needed to define the benefit in smoking cessation.

Tocainide kinetics in congestive heart failure.

Our subjects were 20 patients with life-threatening or symptomatic ventricular arrhythmias refractory to standard oral antiarrhythmic drugs but responsive to intravenous lidocaine. After evaluation of arrhythmias and treatment with intravenous lidocaine, oral tocainide dosage regimens were based on age, weight, and clinical status. During initial tocainide treatment, six plasma tocainide concentrations were recorded within a single dosing interval in 17 of 20 patients, by which standard kinetic parameters were calculated. Eventual trough steady-state tocainide plasma concentrations were predicted from the derived patient-specific kinetic parameters. Mean daily tocainide dose was 1800 mg (1200 to 2400). Mean daily tocainide doses (milligram per kilogram) did not differ significantly among responders and nonresponders or among patients with or without congestive heart failure. Mean peak and trough plasma concentrations 48 hr after initiation of therapy were 9.8 and 7.5 mcg/ml. Tocainide plasma concentrations did not correlate with responders and nonresponders or identify patients who were developing adverse reactions to tocainide. There were no significant differences in any of the calculated kinetic parameters as a function of response to tocainide or the presence of congestive heart failure, but there was a trend toward smaller volumes of distribution and higher average plasma concentrations at steady state in patients with congestive heart failure. There were no significant kinetic differences among patients with and without congestive heart failure, but a trend toward higher plasma concentrations in patients with congestive heart failure and the small number of patients suggests that further data collection is necessary before dosage recommendations can be made.

Clinical significance of exercise-induced bundle branch block.

To evaluate the diagnostic significance and long-term follow-up data of patients with exercise-induced bundle branch block (BBB), 10,176 consecutive patients' exercise test data were reviewed and 50 patients found to have exercise-induced BBB. Clinical, exercise test and arteriographic data were analyzed along with follow-up data during a mean of 43 months. Of the 50 patients, 37 had exercise-induced left BBB and 13 had exercise-induced right BBB. Significant coronary artery disease (CAD) was diagnosed in 26 of 37 patients (70%) with exercise-induced left BBB and in all 13 patients (100%) with exercise-induced right BBB. In patients who underwent coronary arteriography, data demonstrated a high prevalence of proximal left anterior descending disease (17 of 20, 85%). Follow-up data revealed that exercise-induced BBB was associated with a 36% (18 of 50) incidence of coronary events, including 16 patients who underwent coronary artery bypass grafting and 2 hospitalized for congestive heart failure. Results indicated that exercise-induced BBB was infrequent and occurred primarily in association with CAD, had a high prevalence of proximal left anterior CAD, infrequently had similar onset and offset heart rates, was reproducible and associated with a greater incidence of coronary artery bypass grafting than had been previously reported, although the incidence of cardiac events was similar to those investigations.

Clinical characteristics of patients younger than 60 years with mitral anular calcium: comparison with age- and sex-matched control subjects.

The clinical characteristics of 107 patients younger than 60 years with mitral anular calcium (MAC) were compared with those of 107 age- and sex-matched control subjects. The patients with MAC included 55 men and 52 women, mean age 51 years. The control group included 55 men and 52 women, mean age 51 years. Patients with MAC had a higher prevalence of cardiomegaly on chest x-ray (p less than 0.0001), left atrial and left ventricular enlargement by echocardiography (p less than 0.0001), precordial murmurs (p less than 0.0001), diabetes mellitus (p less than 0.0001), systemic hypertension (p less than 0.025) and total conduction defects on surface electrocardiograms (p less than 0.0001) compared with the age- and sex-matched control subjects. The mean serum phosphorus and product of serum calcium and phosphorus were higher in patients with MAC (p less than 0.0025) than in the control subjects. The prevalence of coronary heart disease, aortic stenosis and hypertrophic cardiomyopathy and the mean serum cholesterol, triglyceride, total protein, albumin, creatinine, alkaline phosphatase and calcium levels were not significantly different between patients with MAC and the control subjects.

Early exercise training in patients older than age 65 years compared with that in younger patients after acute myocardial infarction or coronary artery bypass grafting.

To evaluate potential benefits that elderly cardiac patients might gain from early exercise programs, 361 such patients were studied: group I--60 patients aged 44 years or younger; group II--114 patients aged 45 to 54 years; group III--111 patients aged 55 to 64 years; and group IV--76 elderly patients aged 65 years or older. All patients participated in a 12-week exercise program within 6 weeks of acute myocardial infarction or coronary artery bypass grafting. All patients performed symptom-limited exercise tests before and after completion of the exercise program. Between tests, elderly patients manifested significant differences in body weight (76.9 to 75.2 kg), percent body fat (22.3 to 20.8 kg), heart rate at rest (77 to 68 beats/min), maximal heart rate (126 to 138 beats/min), maximal METs (5.3 to 8.1), submaximal average double product (17,305 to 14,071), and submaximal average rating of perceived exertion (12 to 10 [p less than 0.05]). Magnitudes of change were similar among groups, although the elderly patient group had a significantly lower absolute physical work capacity at testing after training than the other 3 groups (p less than 0.05). In the 25 elderly patients who received beta-blocking drugs, METs increased from 5.1 to 7.8 (p less than 0.05). In the remaining 51 elderly patients not receiving beta-blocking drugs, METs increased from 5.4 to 8.2 (p less than 0.05). The magnitude of increase in patients who received beta-blocking drugs was not significantly different from that in patients not receiving beta-blocking drugs.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac conduction defects in patients older than 60 years with aortic stenosis with and without mitral anular calcium.

The prevalence of conduction defects was investigated in 51 patients older than 60 years with aortic stenosis (AS) who underwent aortic valve replacement. Thirty one of the 51 patients, (61%) had associated mitral anular calcium (MAC). The mean age and prevalence of coronary artery disease, systemic hypertension and diabetes mellitus were similar in both groups. The prevalence of conduction defects (atrioventricular block, sinoatrial disease, bundle branch block, left anterior hemiblock or intraventricular conduction defect) was 18 of 31 (58%) in patients with MAC and 5 of 20 (25%) in patients without MAC (p less than 0.025). We conclude that patients older than 60 years with AS have a high prevalence of MAC, and that the prevalence of conduction defects is higher in patients older than 60 years with combined AS and MAC than in patients with AS without MAC.

Digoxin-induced positive exercise tests: their clinical and prognostic significance.

To evaluate the influence of digoxin on the results of exercise testing and the prognostic significance of digoxin-induced positive exercise tests, 98 healthy men, aged 22 to 70 years, were studied. All had normal initial exercise test results. All took digoxin, 0.25 mg daily, for 14 days, and then performed daily exercise tests until each had a negative test response. Five years after these initial tests, a medical history was obtained from 92 of the 98 subjects, and 76 subjects performed repeat exercise tests. Six subjects were lost to follow-up study. Twenty-five percent of subjects (22 of 98) had a digoxin-induced positive exercise test. There was a direct relation between age and the incidence of digoxin-positive tests. The incidence of digoxin-positive tests in men over age 60 years was 100 percent. By 30 seconds after exercise no subject had greater than 1.9 mm S-T depression. No test remained positive for more than 6 minutes after exercise was discontinued. No test was positive 12 days after digoxin was withdrawn. With logistic regression analysis, it was possible to estimate the probability that a subject would have a digoxin-induced positive test. No subject had had a cardiovascular event at follow-up study, but five subjects had a positive repeat exercise test. Four of these subjects had had a digoxin-positive test initially. It is concluded that (1) useful information can be obtained from exercise studies of patients who receive digoxin, (2) the probability that a positive exercise test is due to digoxin can be estimated, (3) to remove the exercise-induced electrocardiographic effect, the drug should be withdrawn for 12 days, and (4) digoxin may unmask subclinical coronary arterial stenosis.

Effect of digoxin on ST-segment changes detected by ambulatory electrocardiographic monitoring in healthy subjects.

Digoxin causes false-positive ST depression during exercise stress testing, but it is unknown if digoxin produces ST depression during ambulatory electrocardiographic monitoring. Fifty healthy volunteers underwent both exercise stress testing and ambulatory electrocardiographic monitoring before and after 14 days of digoxin (0.25 mg/day) administration. Significant ST depression was defined as greater than or equal to 1 mm of horizontal or downsloping ST depression 80 ms after the J point lasting for greater than or equal to 60 seconds. During therapy, 13 subjects (26%) had at least 1 episode of ST depression and 5 subjects (10%) had multiple episodes of ST depression detected by ambulatory monitoring. Ten subjects (20%) had ST depression that occurred during exercise that was detected by both stress test and ambulatory monitoring. Three subjects (6%) had ST depression that was detected on the ambulatory recording only at times other than during the stress test. Stratification of demographic and clinical variables did not predict digoxin-induced ST depression. Thus, digoxin causes false-positive ST depression detected by ambulatory monitoring. The incidence is similar to that observed during stress testing, but also occurs at heart rates lower than that achieved during stress tests. Ambulatory electrocardiographic monitoring will be less useful in the noninvasive assessment of coronary artery disease in patients receiving digoxin.

Significant sex differences in the correlation of electrocardiographic exercise testing and coronary arteriograms.

Two hundred fifty-one patients (195 male and 56 females) referred for evaluation of chest pain were studied by multistage submaximal stress testing and selective coronary arteriography. In men with positive exercise tests the incidence rate of true positive exercise test results--that is, positive tests associated with 75 percent of greater coronary stenosis--was 89 percent in contrast to a 33 percent incidence rate of true positive exercise test results in women. The incidence rate of false positive excercise test results--that is, positive tests associated with no coronary stenosis or less than 50 percent stenosis--was 8 percent in men in contrast to 67 percent in women. Conversely, the incidence rate of false negative exercise test results (that is, negative exercise tests associated with 75 percent or greater coronary stenosis) was higher in men (37 percent) than in women (12 percent). It is concluded that in men a positive multistage stress test is useful in predicting the presence of significant coronary artery disease although a negative stress test cannot be relied upon to rule out the presence of significant disease. In women, a positive exercise test is of little value in predicting the presence of significant coronary artery disease, whereas a negative test is quite useful in ruling out the presence of significant disease. New criteria should be developed for stress testing of women.

Long-term follow-up of patients with echocardiographically detected mitral anular calcium and comparison with age- and sex-matched control subjects.

One hundred seven patients with echocardiographically documented mitral anular calcium (MAC) and 107 age- and sex-matched control subjects without MAC were studied and followed for a mean of 4.4 +/- 2.4 (standard deviation) years. Fourteen (7%) patients were lost to follow-up. Compared with the control group, patients with MAC had higher frequency of precordial murmurs (p less than 0.0001), cardiomegaly (p less than 0.0001), left atrial enlargement (p less than 0.0001), and rhythm and conduction disturbances (p less than 0.0001). During the follow-up, patients with MAC had higher incidence of valve replacement (p less than 0.0025), permanent pacemaker implantation (p less than 0.0025), congestive heart failure (p less than 0.0001), thromboembolic cerebrovascular event (p less than 0.01), sudden death (p less than 0.001) and total cardiac death (p less than 0.0001). However, the frequencies of myocardial infarction, coronary artery bypass surgery and angioplasty, endocarditis or noncardiac death were not significantly different between patients with MAC and the control subjects. Thus, patients with MAC have higher frequencies of precordial murmurs, cardiomegaly, left atrial and ventricular enlargement, rhythm and conduction disturbances. They more frequently undergo valve replacement and permanent pacemaker implantation, develop congestive heart failure and die of cardiac causes than age- and sex-matched control subjects.

Clinical and echocardiographic characteristics of patients with mitral anular calcification. Comparison with age- and sex-matched control subjects.

The clinical and echocardiographic features of 104 patients (53 women and 51 men) with mitral anular calcification (MAC) were compared with those of 121 age- and sex-matched control subjects (62 women and 59 men) without MAC. The incidence of coronary artery disease, rheumatic heart disease, systemic hypertension, and diabetes mellitus was similar in both groups. Patients with MAC had a greater incidence of cardiomegaly (p less than 0.001), cardiac conduction defects (p less than 0.001), and aortic outflow tract murmurs (p less than 0.005) than did control patients. Patients with MAC and without aortic root calcification had a higher incidence (p less than 0.001) of conduction defects than did patients with aortic root calcification without MAC. Control patients with and without aortic root calcification had a similar incidence of conduction defects. A higher incidence of atrioventricular block (p less than 0.025) and bundle branch block or left anterior hemiblock or intraventricular conduction defect (p less than 0.05) was present in anterior MAC than in posterior MAC. In conclusion, patients with MAC have a higher incidence of cardiomegaly, cardiac conduction defects, and aortic outflow tract murmurs than a control group.

Efficacy and tolerance of high-dose intravenous amiodarone for recurrent, refractory ventricular tachycardia.

High-dose intravenous amiodarone was given to 35 patients with recurrent life-threatening ventricular tachycardia (VT) refractory to conventional antiarrhythmic agents. Intravenous amiodarone was given as a 5 mg/kg dose over 30 minutes followed by 20 to 30 mg/kg/day as a constant infusion for 5 days. Twenty-two (63%) patients responded to intravenous amiodarone. All 22 responders received oral amiodarone. Thirteen (59%) continue to receive oral amiodarone after an average follow-up of 19 months, 4 (18%) had sudden cardiac death on oral amiodarone, 2 (9%) died while receiving amiodarone, secondary to left ventricular failure, and 3 (14%) discontinued amiodarone because of side effects. Of the 13 (37%) nonresponders, 10 died in the hospital while receiving intravenous amiodarone, secondary to lethal arrhythmia. Three nonresponders were discharged from the hospital; 2 with automatic cardioverter/defibrillators and 1 receiving a combination of antiarrhythmic agents. Serious adverse events occurred in 13 (37%) patients during intravenous amiodarone therapy. These included hypotension in 8 patients, symptomatic bradycardia in 4 patients and sinus arrest with bradycardia and hypotension in 1 patient. Minor side effects occurred in 23 (66%) patients. In conclusion, high dose intravenous amiodarone is effective in most patients with recurrent, sustained VT but is associated with an unacceptably high incidence of serious adverse events. The optimal dose and duration of intravenous amiodarone for patients with recurrent, refractory sustained VT remain unknown.

Calcific valvular aortic stenosis with and without mitral anular calcium.

Seventy-six consecutive patients, mean age 66 +/- 9 years (+/- standard deviation), with isolated aortic valve replacement for calcific valvular aortic stenosis (AS) were studied. Mitral anular calcium (MAC) was detected by echocardiography in 45 patients (59%). Patients with MAC were older (p less than 0.01), had greater peak systolic aortic valve gradients (p less than 0.025), lower cardiac indexes (p less than 0.025) and smaller valve areas (p less than 0.05) than patients without MAC. Thirty-three percent of patients (15 of 45) with MAC required permanent pacemaker implantation after aortic valve replacement, compared with only 10% of patients (3 of 31) without MAC (p less than 0.025). During the follow-up of 7 years (mean 3.8 +/- 1.6), 27% of patients (12 of 45) with MAC died from cardiac causes, compared to only 7% (2 of 31) without MAC (p less than 0.025). Thus, patients with AS and MAC are older, have more severe AS, more frequently undergo permanent pacemaker implantation after aortic valve replacement and more frequently die of cardiac causes than patients with AS and no MAC during follow-up.

Diagnosing coronary arterial stent thrombosis and arterial closure.

This single-center review of a consecutive series of patients requiring reexamination by angiography within 1 week of a coronary stent placement due to chest pain reveals that patients treated with a poststent anticoagulation regimen of warfarin and aspirin, and those with lower poststent deployment dilation pressures, have an increased risk of subacute stent thrombosis. Repeat cardiac catheterization within the first week after coronary artery stent implantation should be reserved for patients with significant electrocardiographic changes.