A. Teddy Weiss

Transient ischemic dilation of the left ventricle on stress thallium-201 scintigraphy: a marker of severe and extensive coronary artery disease.

On exercise thallium-201 scintigraphy, it has been noted that the size of the left ventricle is sometimes larger on the immediate poststress image than on the 4 hour redistribution image; this phenomenon has been termed transient ischemic dilation of the left ventricle. The angiographic correlates of this finding were assessed in 89 consecutive patients who underwent both stress-redistribution thallium-201 scintigraphy and coronary arteriography. A transient dilation ratio was determined by dividing the computer-derived left ventricular area of the immediate postexercise anterior image by the area of the 4 hour redistribution image. In patients with a normal coronary arteriogram or nonsignificant coronary stenoses (less than 50%), the transient dilation ratio was 1.02 +/- 0.05 and, therefore, an abnormal transient dilation ratio was defined as greater than 1.12 (mean + 2SD). The transient dilation ratio was insignificantly elevated in patients with noncritical coronary artery disease (50 to 89% stenosis) (1.05 +/- 0.05) and in patients with critical stenosis (greater than or equal to 90%) of only one coronary artery (1.05 +/- 0.05). In contrast, in patients with critical stenoses in two or three vessels, the transient dilation ratio was significantly elevated (1.12 +/- 0.08 and 1.17 +/- 0.09, respectively; p less than 0.05 compared with all other patient groups). An abnormal transient dilation ratio had a sensitivity of 60% and a specificity of 95% for identifying patients with multivessel critical stenosis and was more specific (p less than 0.05) than were other known markers of severe and extensive coronary artery disease, such as the presence of multiple perfusion defects or washout abnormalities, or both.(ABSTRACT TRUNCATED AT 250 WORDS)

Early heart rate variability alterations after acute myocardial infarction.

In order to assess early changes in heart rate variability, we studied 81 patients with acute myocardial infarction during the initial 24 hours after thrombolytic therapy. The standard deviation of the mean heart rate and the low (0 to 0.05 Hz), mid (0.05 to 0.20 Hz), and high (0.20 to 0.35 Hz) frequency band power were evaluated with 24-hour ECG Holter recordings. We found diminished variance in the time domain and reduced power spectrum in the frequency domain compared with a group of 41 normal subjects (p < 0.01). Patients with anterior infarction had significantly (p < 0.01) higher heart rates and lower heart rate variability values than patients with inferior infarction. Reduction in heart rate variability occurred within the first 8 hours in patients with anterior infarction; a significant fall (p < 0.03) was especially noted in the high-frequency band after a decline in ST-segment elevation. Heart rate variability alterations in patients with inferior infarction were most evident in the final 8-hour interval. These findings may be viewed in terms of sympathovagal imbalance and may be related to clinical signs of intense autonomic nervous system activity that are observed early in the course of acute anterior and inferior myocardial infarction.

Brain Natriuretic Peptide Levels Predict Perioperative Events in Cardiac Patients Undergoing Noncardiac Surgery: A Prospective Study

Objectives: Brain natriuretic peptide (BNP) levels correlate with prognosis in patients with cardiac disease and may be useful in the risk stratification of cardiac patients undergoing noncardiac surgery (NCS). The objective of this study was to examine whether BNP levels predict perioperative events in cardiac patients undergoing NCS. Methods: Patients undergoing NCS with at least 1 of the following criteria were included: a clinical history of congestive heart failure (CHF), ejection fraction <40%, or severe aortic stenosis. All patients underwent echocardiography and measurement of BNP performed using the ADVIA-Centaur BNP assay (Bayer HealthCare). Clinical endpoints were death, myocardial infarction or pulmonary congestion requiring intravenous diuretics at 30 days of follow-up. Results: Forty-four patients were entered into the study; 15 patients (34%) developed cardiac postoperative complications. The mean BNP level was 1,366 ± 1,420 pg/ml in patients with events and 167 ± 194 pg/ml in patients without events, indicating a highly significant difference (p < 0.001). The ROC area under the curve was 0.91 (95% CI 0.83–0.99) with an optimal cutoff of >165 pg/ml (100% sensitivity, 70% specificity). Conclusions: BNP levels may predict perioperative complications in cardiac patients undergoing NCS, and the measurement of BNP should be considered to assess the preoperative cardiac risk.

One-Stage Coronary Angiography and Angioplasty

The combination of diagnostic angiography and angioplasty as a single procedure is becoming common practice in many institutions, but the feasibility and safety of this strategy have not been reported. This report describes 2,069 patients who underwent coronary angioplasty over a 3-year period at an institution where combined angiography and angioplasty is the norm. All patients were prepared before angiography for potential immediate angioplasty. In 1,719 patients, angioplasty was performed immediately after the diagnostic angiogram, while separate procedures were performed in 350 patients. Of those 350 patients, 254 were referred for angioplasty after diagnostic angiography at other hospitals. One thousand one hundred ninety-seven patients were admitted electively for treatment of stable angina pectoris, and 872 underwent procedures during hospitalization for unstable angina or acute myocardial infarction. One thousand nine hundred seven patients (92.2%) had successful angioplasties; in 130 patients (6.3%) the lesion could not be dilated, but no complication occurred, and in 32 patients (1.5%) angioplasty ended with a major complication (0.8% death, 1.0% Q-wave myocardial infarction, 0.5% emergency coronary artery bypass surgery). There was no difference between the combined and staged groups with regard to success, major and minor complication rates or in length of hospitalization after angioplasty. We conclude that routine combined strategy for angiography and angioplasty is feasible, safe, easier for the patient, and more cost-effective than 2 separate procedures.

Pituitary Apoplexy as a First Manifestation of Pituitary Adenomas Following Intensive Thrombolytic and Antithrombotic Therapy

Apoplexy of a previously asymptomatic pituitary macroadenoma may occur in the setting of intensive thrombolytic, antithrombotic, or anticoagulant therapy for acute myocardial infarction. Classic clinical findings may initially be nonspecific and a high index of suspicion is therefore required for early diagnosis.

Partial resistance to anticoagulation after streptokinase treatment for acute myocardial infarction.

This study examines the response of 3 different groups of patients to anticoagulants: 50 patients previously treated with streptokinase for acute myocardial infarction (AMI) (group 1), 24 patients with AMI who had received anticoagulants without prior thrombolysis (group 2) and 11 subjects who received anticoagulants for noncoronary indications (group 3). No significant differences were detected between groups 2 and 3; therefore, they were combined for analysis. After streptokinase, patients required 37,755 +/- 1,516 (mean +/- standard error of the mean) U of heparin per day to achieve the desired activated partial thromboplastin time (APTT). The dosage was 30,294 +/- 1,089 U/day in patients without antecedent thrombolysis (p less than 0.001). Group 1 patients required 5 +/- 0.4 days until adequate anticoagulation was achieved, compared with 3 +/- 0.2 days in the control group (p = 0.01). Despite higher heparin requirements, group 1 patients had a lower APTT value than the other subjects (87 +/- 5 vs 101 +/- 6 seconds, p = 0.08). Group 1 patients required 5 +/- 0.3 days to reach anticoagulation with warfarin versus 4 +/- 0.2 days in groups 2 + 3 (p = 0.05). Comparison of groups 1 and 2 yielded similar, although smaller, differences. Patients treated with streptokinase for AMI seem to be partially resistant to anticoagulation, which may increase the risk of reocclusion.

Removal of contrast medium from the coronary sinus during coronary angiography: feasibility of a simple and available technique for the prevention of nephropathy

BACKGROUND Contrast-induced nephropathy (CIN) is a major complication of percutaneous coronary interventions with currently limited preventive measures. OBJECTIVES To prevent CIN, we assessed the safety and feasibility of contrast removal from the coronary sinus (CS) during coronary angiography. METHODS We attempted contrast removal on seven patients undergoing coronary angiography with preexisting renal insufficiency (mean serum creatinine=262+/-56 mg%). RESULTS In four patients, a balloon catheter could not be successfully deployed in the CS. In three patients, a balloon catheter with distal side holes was positioned in the CS orifice. The balloon was inflated to occlude the CS concurrent with coronary injections, and 12-16 ml of blood was aspirated after each injection. The procedure appeared to be safe, without adverse events and elevations of serum creatinine levels. Contrast media were effectively withdrawn (44%+/-8%) as assessed by fluoroscopy and dilution of blood. The increased venous pressure at the time of injection reduced coronary flow, allowing for small volumes of administered contrast. CONCLUSIONS Occlusion of the CS during coronary angiography with aspiration of contrast media is safe and effective in reducing contrast load during coronary interventions. This procedure may reduce the risk for CIN in prone patients.

Effect of Severe Aortic Stenosis on the Outcome in Elderly Patients Undergoing Repair of Hip Fracture

Background: The perioperative assessment and management of elderly patients with hip fracture and significant aortic stenosis (AS) is an increasingly common clinical problem with little data available to guide perioperative management. Objectives: It was the aim of this study to examine the incidence of perioperative events in an elderly population of patients with severe AS undergoing repair of hip fracture as compared with controls without severe AS. Methods: Patients over the age of 70 with an echocardiographic diagnosis of severe AS defined as an aortic valve area ≤1.0 cm2 who underwent surgery for hip fracture repair were retrospectively identified. An age-matched group of patients without a history of AS who underwent surgical repair of hip fracture was the control group. The primary outcome of the incidence of postoperative cardiac events defined as death, acute coronary syndrome or pulmonary edema within 30 days was compared. Results: Thirty-two patients with AS (median age 84.5 years, range 72–94; 27 females and 5 males) and 88 controls (median age 86 years, range 80–95; 67 females and 21 males) were entered into the study. There were no significant differences between the AS group and controls for 30-day mortality (6.2 vs. 6.8%) or for the total cardiac event rate (18.7 vs. 11.8%). Conclusions: Our results demonstrate that elderly patients with severe AS can safely undergo repair of hip fractures with a mortality and morbidity comparable with a control population. These patients should not be denied surgery on the basis of their aortic valve disease.

Measurement of Wall Thickness Alone Does Not Accurately Assess the Presence of Left Ventricular Hypertrophy

Clinical echocardiographic assessment of left ventricular hypertrophy (LVH) is generally performed by measuring wall thickness alone (WT). The objective of this study was to compare the assessment of LVH using the measurement of WT to that using indexed LV mass. Hypertensive patients underwent echocardiography with the measurement of LV WT and LV mass. For each patient, the presence of LVH was assessed by both methods with WT compared to the gold standard of LV mass index. In all, 92 patients (51M/41F) were entered, and in only 55 patients (60%) were the two methods concordant. There was a tendency for WT to underestimate LVH in females (sensitivity 37%, specificity 79%) and overestimate LVH in males (sensitivity 88%, specificity 56%). The measurement of WT alone overestimates LVH in males and underestimates LVH in females and should not be used as a surrogate marker for increased LV mass.

Influence of coronary angioplasty on the progression of coronary atherosclerosis

This study examines the effect of coronary angioplasty on the progression and appearance of new disease in sites of the coronary tree that were not dilated by the balloon. We examined 355 pairs of coronary angiograms from 252 patients. The study consisted of consecutive patients who were referred for catheterization > 1 month after successful angioplasty. Progression/regression and the appearance of new narrowings at sites not dilated by angioplasty were determined. The life-table method was used to determine outcome, and any event (progression, regression, and new narrowing) was analyzed according to the time of occurrence. The angioplasty artery was compared with the non-angioplasty artery and the effect of restenosis was determined by comparing arteries with and without restenosis. Progression/regression rates were not significantly different in angioplasty and non-angioplasty arteries. More new narrowings were identified in the angioplasty artery (p < 0.01). With regard to narrowings located in the angioplasty artery, progression was more common, regression less common, and the appearance of new narrowings more common in arteries with restenosis than in non-angioplasty arteries or arteries without restenosis. We believe that mechanical trauma to the artery during angioplasty could accelerate disease progression and the appearance of new narrowings in angioplasty arteries, whereas normalization of flow rate and pattern, especially in arteries without restenosis, attenuates the rate of progression and the appearance of new narrowings in these arteries. The final outcome depends on the balance between these factors.