Acute myocardial infarction following sildenafil citrate (Viagra) intake in a nitrate-free patient

Since its introduction to the market in March 1997, sildenafil acetate (Viagra) has been prescribed to 1.7 million people. Sixteen men who were taking the drug have died, 7 of them during or soon after sexual activity. Most of these data have been derived from the media and not from the scientific literature. There is a general impression that cardiovascular complications of sildenafil occur mainly when the drug is taken concomitantly with nitrates. We describe a 65-year-old man with known coronary artery disease who had an acute myocardial infarction shortly after taking sildenafil and engaging an sexual activity. The patient had not been using nitrates. We suggest that the emotional arousal induced by Viagra, followed by the heavy physical exertion during sexual activity, triggers plaque rupture that leads to acute myocardial infarction.

Atrial natriuretic peptide levels after different types of inferior wall myocardial infarction

BACKGROUND

Atrial natriuretic peptide (ANP) is released from cardiac atrium secondary to increased atrial pressure. The plasma levels of ANP have been found to be related to short- and long-term prognosis after acute myocardial infarction (MI). The purpose of the present study was to investigate the plasma levels of ANP in three groups of patients with inferior wall acute MI classified according to ST-segment depression in the precordial leads.

METHODS

The study population consisted of 18 patients with inferior wall acute MI classified into three types: Type 1 = no precordial ST-segment depression (7 patients), Type 2 = sum of ST-segment depression in leads V1 to V3 equal to or more than the sum of ST-segment depression in leads V4 to V6 (4 patients), and Type 3 = maximal precordial ST-segment depression in leads V4 to V6 (7 patients).

RESULTS

Radioimmunoassay showed that plasma ANP levels were significantly higher in patients with Type 3 acute inferior wall myocardial infarction compared with those with Types 1 and 2 (313.1 +/- 233, 73.0 +/- 27.5), and 84 +/- 32.7 pg/ml, respectively, p = 0.018).

CONCLUSIONS

Plasma ANP levels are higher in patients with Type 3 acute inferior wall MI compared with patients with Types 1 and 2. These findings, together with earlier ones, may contribute to our understanding of the pathophysiology of the presence of ST-segment depression in the precordial leads in inferior wall acute MI.

Increased adhesiveness of white blood cells in patients with unstable angina: additional evidence for an involvement of the immune-inflammatory system

BACKGROUND

Data are being accumulated on the presence of inflammatory response in patients with acute coronary syndromes.

HYPOTHESIS

The study was undertaken to confirm that the adhesive state of the peripheral blood leukocytes can provide information on an inflammatory process in patients with unstable angina pectoris.

METHODS

The study included 21 patients with unstable angina, 32 patients with stable angina, and 13 patients with chest pain and no evidence of coronary artery disease.

RESULTS

The percentage of aggregated leukocytes in patients with unstable angina (5.8 +/- 3.2%) was significantly (p < 0.02) increased compared with that of patients with no evidence of active coronary disease (3.2 +/- 2.6%).

CONCLUSION

Additional evidence for an existing smoldering inflammatory process in unstable angina pectoris can be provided by testing the percentage of aggregated leukocytes in peripheral blood.

Acute anterior wall myocardial infarction entailing ST-segment elevation in lead V1: electrocardiographic and angiographic correlations

BACKGROUND

The correlation between ST elevation in lead V1 during anterior wall acute myocardial infarction (AMI) and the culprit lesion site in the left anterior descending (LAD) coronary artery is poor.

HYPOTHESIS

The study was undertaken to assess the electrocardiographic (ECG) characteristics and angiographic significance of ST-segment elevation in lead V1 during anterior wall acute myocardial infarction (AMI).

METHODS

Data from 115 patients with anterior wall AMI, who underwent coronary angiography within 14 days of hospitalization, were studied. The admission 12-lead ECG was examined and the coronary angiogram was evaluated for the nature of the conal branch of the right coronary artery (RCA) and for the culprit lesion site in the left anterior descending (LAD) coronary artery.

RESULTS

Mean ST-segment deviation and the frequency of patients with ST-segment elevation > 0.1 mV were significantly lower in lead V1 than in lead V2 (0.136 +/- 0.111 mV vs. 0.421 +/- 0.260 mV, and 37 vs. 96%, for leads V1 and V2, respectively). A small conal branch not reaching the interventricular septum (IVS) was more prevalent among patients with ST-segment elevation > 0.1 mV in lead V1 (67%), whereas a large conal branch was more prevalent in patients with ST-segment deviation (1 mV in that lead (83%, p < 0.001). No relation was found between ST-segment deviation in lead V1 during anterior wall AMI and the culprit lesion site in the LAD.

CONCLUSION

ST-segment elevation in lead V1 during first anterior wall AMI was found in one third of the patients, and its magnitude was lower than that in the other precordial leads. ST-segment elevation in lead V1 favors the presence of a small conal branch of the RCA that does not reach the IVS.

Abnormal Q waves on the admission electrocardiogram of patients with first acute myocardial infarction: prognostic implications

BACKGROUND

Q waves developed in the subacute and persisting into the chronic phase of myocardial infarction (MI) usually signify myocardial necrosis. However, the mechanism and significance of Q waves that appear very early in the course of acute MI (< 6 h from onset of symptoms), especially if accompanied by ST elevation, are probably different.

HYPOTHESIS

This study assesses the prognostic implications of abnormal Q waves on admission in 2,370 patients with first acute MI treated with thrombolytic therapy < 6 h of onset of symptoms.

RESULTS

Patients with abnormal Q waves in > or = 2 leads with ST-segment elevation (n = 923) were older than patients without early Q waves (n = 1,447) (60.6 +/- 11.9 vs. 58.8 +/- 11.9 years, respectively; p = 0.0003), and had a greater incidence of hypertension (34.3 vs. 30.5%; p = 0.05) and anterior MI (60.6 vs. 41.1%; p < 0.0001). Time from onset of symptoms to therapy was longer in patients with Q waves upon admission (208 +/- 196 vs. 183 +/- 230 min; p = 0.01). Peak serum creatine kinase (2235 +/- 1544 vs. 1622 +/- 1536 IU; p < 0.0001), prevalence of heart failure during hospitalization (13.8 vs. 7.0%, p < 0.0002), hospital mortality (8.0 vs. 4.6%; p = 0.02), and cardiac mortality (6.6 vs. 4.5%, p = 0.11) were higher in patients with anterior MI and with abnormal Q waves than in those without abnormal Q waves upon admission. There was no difference in peak creatine kinase, prevalence of heart failure, in-hospital mortality, and cardiac mortality between patients with and without abnormal Q waves in inferior MI. Multivariate regression analysis confirmed that mortality is independently associated with presence of Q waves on admission (odds ratio 1.61; 95% CI 1.04-2.49; p = 0.04 for all patients; odds ratio 1.65; 95% CI 0.97-2.83; p = 0.09 for anterior wall MI.

CONCLUSION

Abnormal Q waves on the admission electrocardiogram (ECG) are associated with higher peak creatine kinase, higher prevalence of heart failure, and increased mortality in patients with anterior MI. Abnormal Q waves on the admission ECG of patients with inferior MI are not associated with adverse prognosis.

Value of T-wave direction with lead III ST-segment depression in acute anterior wall myocardial infarction: electrocardiographic prediction of a "wrapped" left anterior descending artery

BACKGROUND

Lead III ST-segment depression during acute anterior wall myocardial infarction (AMI) has been attributed to reciprocal changes. However, the value of the T-wave direction (positive or negative) in predicting the site of obstruction and type of the left anterior descending (LAD) artery is not clear and has not been studied before.

HYPOTHESIS

The aim of the study was to assess retrospectively the correlation between two patterns of lead III ST-segment depression, and type of LAD artery and its level of obstruction during first AMI.

METHODS

The study group consisted of 48 consecutive patients, admitted to the coronary care unit for first AMI, who showed ST-segment elevation in lead a VL and ST-segment depression in lead III on admission 12-lead electrocardiogram. The patients were divided by T-wave direction into Group 1 (n = 31), negative T wave, and Group 2 (n = 17), positive T wave. The coronary angiogram was evaluated for type of LAD ("wrapped", i.e., surrounding the apex or not), site of obstruction (pre- or postdiagonal branch), and other significant coronary artery obstructions.

RESULTS

Mean lead III ST-segment depression was 1.99 +/- 1.32 mm in Group 1 and 1.13 +/- 0.74 mm in Group 2 (p = 0.004); mean ST-segment elevation in a VL was 1.35 +/- 0.84 mm and 1.23 +/- 0.5 mm, respectively (p = 0.5). A wrapped LAD was found in 12 patients (38.7%) in Group 1 and in 13 in Group 2 (76.4%) (p = 0.02). The sensitivity of lead III ST-segment depression with positive T wave to predict a wrapped LAD was 52%, and the specificity was 82% with a positive predictive value of 76%. On angiography, 25 patients (80%) in Group 1 and 13 (76%) in Group 2 had prediagonal occlusion of the LAD (p = 0.77). No significant difference between groups was found for right and circumflex coronary artery involvement or incidence of multivessel disease.

CONCLUSIONS

The presence of lead III ST-segment depression with positive T wave associated with ST-segment elevation in a VL in the early course of AMI can serve as an early electrocardiographic marker of prediagonal occlusion of a "wrapped" LAD.

Predictive value of dobutamine radionuclide ventriculography in detection of functional improvement after acute anterior wall infarction and thrombolytic therapy

BACKGROUND

Prolonged postischemic ventricular dysfunction (stunned myocardium) may prevent the assessment of myocardial salvage early after thrombolysis. Dobutamine in conjunction with radionuclide ventriculography has been proposed for the early assessment of myocardial viability and prediction of functional recovery.

HYPOTHESIS

This study was designed to investigate the effects of low-dose dobutamine infusion on early global and regional function of reperfused myocardium after acute anterior wall myocardial infarction (MI). In particular, our purpose was to examine whether this response can predict late recovery of left ventricular function and correlate with the reperfused status (patency of infarct-related artery).

METHODS

In all, 29 consecutive patients with first uncomplicated anterior wall MI, and who had received thrombolytic therapy, underwent radionuclide ventriculography at rest and 2 min after each dose increment of dobutamine infusion (5-15 micrograms/kg/min) on the third day after the infarction, at discharge, and at 3 months' follow-up. Global and regional ejection fraction were calculated at each stage. Four patients with complications were dropped from the study. A significant response to dobutamine was defined as an increase of at least > or = 7% in global or regional ejection fraction at the infarct zones.

RESULTS

Of the 25 patients, 18 (72%) fulfilled these criteria. Of these, 10 patients (56%) had a significant improvement in global or regional ejection fraction at discharge and 13 patients (72%) at 3-month follow-up. The overall sensitivity of the dobutamine test in predicting left ventricular improvement was 100% at discharge and 93% at 3-month follow-up. However, the positive and negative predictive values were 56 and 100% at discharge and 72 and 86%, respectively, at 3-month follow-up.

CONCLUSION

Low-dose dobutamine radionuclide ventriculography is a safe and useful test for assessing myocardial viability and may predict late functional improvement in patients with anterior wall MI.

The grades of ischemia on the presenting electrocardiogram of patients with ST elevation acute myocardial infarction

Patients with acute myocardial infarction who have terminal QRS distortion in addition to ST-segment elevation (grade III ischemia) on their presenting electrocardiogram have higher mortality and larger final infarct size than patients with ST-segment elevation without changes in the terminal portion of the QRS complex (grade II ischemia). This article discusses the data concerning the prognostic significance of the grades of ischemia on the presenting electrocardiogram and the possible underlying mechanism of terminal QRS distortion. Patients with grade III ischemia have more severe ischemia and faster progression of necrosis than patients with grade II ischemia. This might be related to less protection by "ischemic preconditioning" or presence of collateral circulation.

Insulin resistance is increased by transdermal estrogen therapy in postmenopausal women with cardiac syndrome X

Estrogen has been reported to have both short- and long-term effects on the cardiovascular system. However, it remains to be examined how short-term transdermal estrogen therapy (TET) affects insulin sensitivity (SI) in patients with cardiac syndrome X (CSX), who are characterized by elevated insulin resistance. SI was assessed in a randomized, double-blind, placebo-controlled crossover study by minimal model analysis in seven postmenopausal women with CSX treated by TET. SI decreased by 32 +/- 8.3%, from 5.94 +/- 1.14 at baseline to 3.61 +/- 0.40 [(10(-4) x min(-1))/(microU/ml)] during TET (p = 0.03). Time to the onset of symptoms increased from 414.2 +/- 51.0 s at baseline to 450.0 +/- 53.2 s (p = 0.04). We conclude that TET increases SI in postmenopausal women with CSX. This effect is unrelated to the beneficial anti-ischemic effects on exercise duration.

Early development of high-degree atrioventricular block in inferior acute myocardial infarction is predicted by a J-point/R-wave ratio above 0.5 on admission

This study assessed the ability of simple clinical and electrocardiographic (ECG) variables routinely obtained on admission to identify patients with inferior myocardial infarction who are at high risk of developing high-degree atrioventricular (AV) block within the first 24 h of hospitalization in 205 patients. The admission ECGs were classified into two patterns based on the J-point to R-wave amplitude ratio: pattern 1: those with J-point/R-wave ratio <0.5; pattern 2: patients with J-point/R-wave ratio >/=0.5 in >/=2 inferior leads (II, III and aVF). High-degree AV block was found in 10.2% of the patients (21 of 205 patients; 5 and 16% of the patients with initial patterns 1 and 2, respectively, p = 0.014). Multivariate logistic regression analysis revealed that the only variables independently associated with high-degree AV block were the initial ECG pattern 2 versus 1 (odds ratio, OR, 4.47, 95% confidence interval, CI, 1.18-16.9; p = 0.0276), age (OR 1.06, 95% CI 1.01-1.12; p = 0.0254); Killip class >1 (OR 2.33, CI 0.83-6. 54; p = 0.1065) and thrombolytic therapy (OR 0.32, 95% CI 0.11-0.93; p = 0.037).

Are there differences among patients with inferior acute myocardial infarction with ST depression in leads V2 and V3 and positive versus negative T waves in these leads on admission?

We assessed whether there are differences among patients with inferior acute myocardial infarction and ST segment depression in leads V2-V3 between those with positive versus negative T waves on admission. We found no differences in the prevalence of concomitant significant left anterior descending coronary artery stenosis and anterior or posterior wall motion abnormalities on echocardiography between the two groups. Precordial ST segment depression with negative T wave may be the early electrocardiographic pattern of posterior infarction, reflecting ST segment elevation with positive T waves that would have been detected by leads facing the posterior wall.

Value of the initial electrocardiogram in patients with inferior-wall acute myocardial infarction for prediction of multivessel coronary artery disease

BACKGROUND

Patients with inferior-wall acute myocardial infarction (AMI) who have ST-segment depression in the left precordial leads (LSTD+) on the initial electrocardiogram were reported to have more diffuse coronary artery disease (CAD) than had those without this finding (LSTD-). This suggests that LSTD+ patients may need extensive revascularization interventions more often than do LSTD- patients. However, this has not yet been confirmed.

OBJECTIVE

To compare the coronary angiographic findings and treatment strategies for patients with inferior-wall AMI according to the LSTD pattern.

METHODS

The clinical outcomes and the angiographic findings for 238 consecutive patients aged < or = 75 years who had been admitted to our hospital between 1 February 1995 and 1 February 1997 with inferior-wall AMI were retrospectively analyzed. The patients were divided into two groups according to the pattern of precordial ST-segment depression: LSTD+, ST-segment depression in leads V4-V6; and LSTD-, absence of this finding. All patients were treated according to current practice guidelines including with thrombolysis and revascularization interventions.

RESULTS

The final study population included 217 patients; 83 were LSTD+ and 134 were LSTD-. All underwent coronary angiography within 30 days of the infarction. Compared with LSTD- patients, LSTD+ patients tended to be older (mean age 62.7 +/- 11.7 versus 58.3 +/- 9.6 years, P = 0.004), and had higher incidences of hypertension (39.8 versus 24.6%, P = 0.019) previous myocardial infarction (45.8 versus 20.1%, P = 0.0001) and congestive heart failure (21.7 versus 3.7%, P = 0.00008). Three-vessel CAD was much more common, and single-vessel CAD much less common, in the LSTD+ than in LSTD- group (62.7 versus 13.4% and 8.4 versus 50.7%, P < 0.00001 for both). Coronary-artery-bypass surgery and multivessel percutaneous coronary interventions (PCI) were used in treating 65.1% of the LSTD+ versus only 6.0% of the LSTD- patients (P < 0.00001), whereas single-vessel PCI was used in treating 71.6% of the LSTD- patients versus only 24.1% of the LSTD+ patients (P < 0.00001). Thus, the LSTD- pattern predicted single-vessel disease and single-vessel PCI only, whereas the LSTD+ pattern was predictive of multivessel CAD and of use of coronary-artery-bypass surgery or multivessel PCI (predictive values of 94.0 and 65.1%, respectively).

CONCLUSIONS

Among patients with inferior-wall AMI, left precordial ST-segment depression predicts a very high prevalence of multivessel CAD and use of extensive revascularization interventions. The absence of this finding predicts nondiffuse CAD and lack of a need for extensive revascularization.

The prognostic implications of negative T waves in the leads with ST segment elevation on admission in acute myocardial infarction

We assessed the prognostic significance of negative T waves on admission in leads with ST elevation in 2,853 patients with acute myocardial infarction treated with thrombolysis. Patients were classified into 2 groups based on the presence of negative (T-) or positive (T+) T waves in the leads with ST elevation on admission. T+ and T- waves on admission were detected in 2,601 (91%) and 252 (9%) patients, respectively. T- waves were observed in 6.7 and 9.6% of patients admitted </=2 and 2-6 h after onset of infarction, respectively. There was a difference in prognosis between patients admitted </=2 and >2 h after symptom onset. T- patients admitted </=2 h after onset had no hospital mortality (0/52 patients), as compared to a 5.0% mortality rate in T+ patients (36/726 patients; p = 0.19). T- patients treated >2 h after onset suffered higher mortality (20/196 patients; 10.2%) than T+ patients (100/1,836 patients; 5.4%; p = 0.01). Multivariate analysis of the data on patients treated >2 h after onset demonstrated T- waves to be associated with mortality (OR 1.86; 95% CI 1.07-3.25; p = 0.017). T- waves in leads with ST elevation upon admission are associated with adverse prognosis in patients presenting >2 h after symptom onset, whereas in patients presenting </=2 h after first symptoms, T- waves may be associated with better prognosis.

Thrombolysis is an effective and safe therapy in stuck bileaflet mitral valves in the absence of high-risk thrombi

OBJECTIVES

We sought to evaluate the effectiveness and safety of thrombolytic therapy in stuck mitral bileaflet heart valves in the absence of high-risk thrombi.

BACKGROUND

Current recommendations for the thrombolytic treatment of stuck prosthetic mitral valves are partially based on older valve models and inclusion of patients in whom high-risk thrombi were either ignored or not sought for. The feasibility and safety of thrombolysis in bileaflet models may be affected by the predilection of thrombi to catch the leaflet hinge.

METHODS

We studied 12 consecutive patients (men/women = 5/7, age 58.8 +/- 14.9 years) who experienced one or more episodes of stuck bileaflet mitral valve over a 33-month period and received thrombolytic therapy with streptokinase, urokinase or tissue-type plasminogen activator. Transesophageal echocardiography was performed in all patients. Patients with mobile or large (>5 mm) thrombi were excluded. Functional class at initial episode was I-II in 4 patients (33.3%) and III-IV in 8 patients (66.6%).

RESULTS

Patients receiving thrombolytic therapy achieved an overall 83.3% freedom from a repeat operation or major complications (95% confidence interval 51.6-97.9%). Minor bleeding occurred in three patients (25%) and allergic reaction in one (8.3%). Transient vague neurologic complaints, without subjective findings, occurred in four patients (33.3%). Three patients had one or more relapses within 5.2 +/- 3.1 months from the previous episode, and readministration of thrombolytics was successful.

CONCLUSIONS

In clinically stable patients with stuck bileaflet mitral valves and no high-risk thrombi, thrombolysis is highly successful and safe, both in the primary episode and in recurrence. The best thrombolytic regimen is yet to be established.

Relation between evolutionary ST segment and T-wave direction and electrocardiographic prediction of mycardial infarct size and left ventricular function among patients with anterior wall Q-wave acute myocardial infarction who received reperfusion therapy

In the prethrombolytic era it was found that infarct size and left ventricular ejection fraction could be predicted using the Selvester QRS score. We evaluated whether infarct size and left ventricular ejection fraction could be predicted by the predischarge QRS score in patients who had received reperfusion therapy and whether considering the configuration of the ST segments and T waves would increase the accuracy of these predictions. We evaluated 51 patients with first anterior wall myocardial infarction who had received reperfusion therapy and predischarge resting technetium-99m-sestamibi scan. The electrocardiograms recorded on the same day of the scan were analyzed for the QRS score and were divided into 3 groups: A, isoelectric ST and negative T waves; B, ST elevation (> or =0.1 mV) and negative T waves; and C, ST elevation (> or =0.1 mV) and positive T waves. Groups A, B, and C included 12, 23, and 16 patients, respectively. The myocardial perfusion defect extent increased from groups A to C (median 21%, 37%, and 43.5% in groups A, B, and C, respectively; p = 0.023). Similarly, left ventricular ejection fraction decreased (44%, 38%, and 34%, respectively; p = 0.042) from groups A to C. Overall, the correlation between the QRS score and the myocardial perfusion defect extent (rho 0.249; p = 0.08) and ejection fraction (rho -0.229; p = 0.11) was poor. A statistically significant correlation between myocardial perfusion defect size and QRS score was found only in group A (rho 0.599, p = 0.04). Among patients with anterior myocardial infarction who received reperfusion therapy, the predischarge QRS score was predictive of infarct size only in those in whom ST elevation resolved completely. In patients with residual ST elevation there was no correlation between QRS score and infarct size.

Persistent ST segment depression in precordial leads V5-V6 after Q-wave anterior wall myocardial infarction is associated with restrictive physiology of the left ventricle

OBJECTIVES

To examine the relationship between the persistence of ST segment depression in leads V5-V6 after Q-wave anterior wall myocardial infarction (MI) and the filling pattern of the left ventricle (LV).

BACKGROUND

Precordial ST segment depression predominantly in leads V5-V6 is associated with increased in-hospital morbidity and mortality after acute myocardial ischemia, perhaps due to reduced diastolic distensibility of the LV.

METHODS

We prospectively studied 19 patients after Q-wave anterior wall MI (>6 months). All patients underwent 12-lead ECG recording, symptom-limited treadmill exercise testing with single photon emission computed tomography thallium-201 imaging, transthoracic Doppler echocardiography, cardiac catheterization and measurement of circulating atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels. Patients were classified based on the presence of ST segment depression in leads V5-V6: Group I = ST segment depression <0.1 mV (n = 10); Group II = ST segment depression > or =0.1 mV (n = 9).

RESULTS

Patients in Group II had greater LV end diastolic pressures (32.4 +/- 6.5 mm Hg vs. 14.8 +/- 6.1 mm Hg; p = 0.0001), higher plasma ANP (44.4 +/- 47.1 pg/ml vs. 10.7 +/- 14 pg/ml; p = 0.04) and BNP levels (89.4 +/- 62.7 pg/ml vs. 23.6 +/- 33.1 pg/ml; p = 0.01), greater left atrium area (20.6 +/- 3.1 cm2 vs. 17.8 +/- 2.4 cm2; p = 0.05), lower peak atrial (A), higher early (E) mitral inflow velocities, a higher E/A ratio and a lower deceleration time (167 +/- 44 ms vs. 220 +/- 40 ms; p = 0.05). Lung thallium uptake during exercise was more common in Group II (78% vs. 10%, p = 0.04).

CONCLUSIONS

Persistent ST segment depression in leads V5-V6 in survivors of Q-wave anterior wall MI is associated with increased LV filling pressure and a restrictive LV filling pattern.

Comparison of the pharmacokinetics of fosinoprilat with enalaprilat and lisinopril in patients with congestive heart failure and chronic renal insufficiency

AIMS

To compare the serum pharmacokinetics of fosinoprilat with enalaprilat and lisinopril after 1 and 10 days of dosing with fosinopril, enalapril and lisinopril.

METHODS

Patients with congestive heart failure (CHF, NYHA Class II-IV) and chronic renal insufficiency (creatinine clearance </=30 ml min-1 ) were randomized to receive fosinopril, enalapril or lisinopril in two parallel-group studies. In the first study 24 patients were treated with 10 mg fosinopril (n=12 patients) or 2.5 mg enalapril (n=12) every morning for 10 consecutive days. In the second study 31 patients were treated with 10 mg fosinopril (n=16 patients) or 5 mg lisinopril (n=15) every morning for 10 consecutive days. Samples of blood were collected for determination of pharmacokinetic parameters. The area under the curve (AUC) between the first and last days of treatment and the accumulation index (AI) were the primary outcome measures.

RESULTS

All three angiotensin converting enzyme (ACE) inhibitors exhibited a significant increase in AUC between the first and last days of treatment in both studies. The difference between the AI for fosinoprilat (1.41) and enalaprilat (1.96) was statistically significant (95% CI: 1.05, 1.84). Similarly, the difference between the AI for fosinoprilat (1.21) and lisinopril (2.76) was statistically significant (95% CI: 1.85, 2.69). All three ACE inhibitors completely inhibited serum ACE for 24 h. All treatments were well tolerated.

CONCLUSIONS

Fosinoprilat exhibits significantly less accumulation than enalaprilat or lisinopril in patients with CHF and renal insufficiency, most probably because fosinoprilat is eliminated by both the kidney and liver, and increased hepatic elimination can compensate for reduced renal clearance in patients with kidney dysfunction.

Effect of isosorbide-5-mononitrate on exercise performance and clinical status in patients with congestive heart failure. Results of the Nitrates in Congestive Heart Failure (NICE) Study

BACKGROUND AND AIMS

Nitrate therapy improves hemodynamics in patients with heart failure, but the chronic effects of oral nitrates on exercise performance and clinical status have not been well studied.

METHODS

Oral isosorbide-5-mononitrate (ISMN) (50 mg once daily) or placebo was administered to 136 patients (NYHA Class 2-3) treated for heart failure, all receiving captopril and most also furosemide. Endpoints were treadmill exercise time at 12 weeks by modified Naughton protocol (primary), with an additional 12-week follow-up period. Secondary endpoints included left ventricular dimensions, ejection fraction, cardiothoracic ratio, functional class, quality of life, hospitalizations and plasma norepinephrine and atrial natriuretic peptide in a four-center substudy.

RESULTS

Intention-to-treat analysis showed that mean change in treadmill exercise duration tended to be greater in patients receiving ISMN than placebo (treatment difference +42 s, 95% CI -5, +90 s at 12 weeks and +21 s, 95% CI -25, +74 s after 24 weeks) (NS). Treatment difference was greater in the prespecified subgroup with ejection fraction 31-40% (+55 s, 95% CI -11, +136 s at 12 weeks and +65 s, 95% CI +3, +147 s) (p = 0.035) at 24 weeks. No deleterious effects (i.e. hypotension) were observed with ISMN, although headache was reported in 19% of the active treatment group (p = 0.0001).

CONCLUSIONS

ISMN added to captopril increased treadmill exercise time in patients with heart failure and a lesser reduction in baseline ejection fraction, although for the group as a whole, the increase in treadmill time was not significant.

Electrocardiographic criteria for predicting the culprit artery in inferior wall acute myocardial infarction

Two patterns of the QRS complex in the lateral lead aVL on the admission electrocardiograms of patients with inferior wall acute myocardial infarction (AMI) were correlated with the culprit artery. S/R wave ratio < or =1/3 with ST depression < or =1 mm was found to be a sensitive and specific marker for left circumflex artery AMI, whereas S/R-wave ratio >1/3 with ST-segment depression >1 mm was suggestive of right coronary artery AMI.

Usefulness of dobutamine radionuclide ventriculography for prediction of left ventricular function improvement after coronary artery bypass grafting for ischemic cardiomyopathy

Ventricular function may improve after coronary artery bypass grafting (CABG) in patients with ischemic cardiomyopathy depending on the amount of contractile myocardial reserve. Based on the studies using dobutamine echocardiography to predict regional wall improvement after revascularization, we investigated the benefit of low-dose dobutamine radionuclide ventriculography for assessing functional contractile reserve in this population. The study group included 56 patients with ischemic cardiomyopathy (mean left ventricular [LV] ejection fraction [EF] of 23 +/- 5%) and multivessel disease, who were referred for viability assessment. All underwent radionuclide ventriculography before and during infusion of 5 and 10 microg/kg/min of dobutamine. An increase in global LVEF from rest to dobutamine was calculated, and 10% was considered the cutoff value to predict ventricular improvement after CABG. Of the 35 patients who underwent CABG 1 month later, 29 were available for repeated radionuclide ventriculography after 12 +/- 5 months. Of these, 15 showed improvement (delta LVEF > or = 5%, mean 10 +/- 5%) and 14 did not (delta LVEF < 5%, mean -1 +/- 3%). The increase in EF with dobutamine had the highest univariate predictive value of all parameters evaluated. The sensitivity, specificity, and positive and negative predictive values of dobutamine radionuclide ventriculography were 67%, 93%, 91%, and 72%, respectively. We conclude that dobutamine radionuclide ventriculography is a useful method to assess contractile reserve and predict ventricular functional improvement after CABG in patients with ischemic cardiomyopathy.

Correlation of angiographic findings and right (V1 to V3) versus left (V4 to V6) precordial ST-segment depression in inferior wall acute myocardial infarction

This study assessed whether differences in the underlying mechanisms for various patterns of precordial ST-segment depression with inferior acute myocardial infarction (AMI) are associated with poorer prognoses. We studied 1,155 patients with inferior AMI who underwent thrombolysis in the Global Utilization of Streptokinase and TPA for Occluded arteries (GUSTO-I) angiographic substudy: those without precordial ST depression (n = 412; 35.7%), those with maximum ST depression in leads V1 to V3 (n = 547; 47.4%), and those with maximum ST depression in leads V4 to V6 (n = 196; 17.0%) on admission electrocardiogram. We compared the infarct-related artery, presence of left anterior descending or multivessel coronary artery disease, and left ventricular function among groups. Patients with maximum ST depression in leads V4 to V6 more often had 3-vessel disease (26.0%) than those without precordial ST depression (13.5%) or those with ST depression in leads V1 to V3 (15.7%; p = 0.002), and they had a lower ejection fraction (median 54% vs 60% and 55%, respectively; p <0.001). Patients with maximum ST depression in leads V1 to V3 less often had AMIs due to proximal right coronary artery obstruction (23.9%) than patients without precordial ST depression (35.2%) or those with ST depression in leads V4 to V6 (40.0%; p = 0.001) and had larger AMIs as estimated by peak creatine kinase. Different patterns of precordial ST depression are associated with distinctive coronary anatomy. ST depression in leads V4 to V6, but not V1 to V3, confers a greater likelihood of multivessel coronary artery disease.

Relation between QT dispersion and slow intraventricular conduction in patients with acute anterior wall myocardial infarction

BACKGROUND

QT dispersion has been proposed as a simple, noninvasive measure for identifying patients at risk of postinfarction arrhythmia. It is assumed to reflect nonuniform ventricular repolarization, which, in turn, may result from regional differences in repolarization time as well as from localized activation delay. The aim of this study was to examine the relation between QT dispersion and intraventricular conduction abnormalities in patients with acute anterior wall myocardial infarction.

METHODS AND RESULTS

Standard 12-lead electrocardiographic and 12-lead signal-averaged electrocardiographic recordings were performed in 25 patients with a first Q-wave anterior wall myocardial infarction. Measures calculated by using the 6 precordial (V1 through V6) leads for QT dispersion were (1) difference between maximum and minimum QT and QTc intervals and (2) standard deviation of QT and QTc intervals. Measures calculated from the signal-averaged electrocardiogram were (1) maximum filtered QRS duration; (2) mean; and (3) standard deviation of filtered QRS duration. No relation was found between any measure of filtered QRS duration and that of QT dispersion by using linear correlation analysis. Similarly, no significant association was demonstrated between the filtered QRS duration and corresponding QT interval measurements (total 131 leads).

CONCLUSIONS

The lack of correlation between signal-averaged electrocardiogram indexes of slow intraventricular conduction and electrocardiogram variables of QT dispersion suggests an independent predictive value for the 2 methods in identifying patients at risk of postinfarction arrhythmia. This suggestion is further supported by the finding that altered activation sequence is an unlikely mechanism of QT dispersion in patients with acute myocardial infarction, as indicated by the lack of association between the filtered QRS duration and corresponding QT interval measurements.

Coronary stent deployment without predilation: prevention of complications of venous graft angioplasty

Saphenous vein graft stenting without predilation may potentially decrease procedural complications such as distal embolization and no-reflow phenomenon. In this report the authors describe the deployment of stents (three Wallstents, one Palmaz-Schatz, one Multilink, and one NIR) without predilation in five patients with unstable angina pectoris due to high-grade stenosis in old saphenous vein grafts. Stent deployment was successful in all patients without procedure-related complications. Stenting without predilation appears to be feasible in old bypass grafts with significant stenosis. The potential of this new stenting technique to reduce the risk of stenting complications should be tested by a randomized trial.

QRS complex distortion predicts no reflow after emergency angioplasty in patients with anterior wall acute myocardial infarction

BACKGROUND

In patients with acute myocardial infarction, distortion of the terminal portion of the QRS complex on the electrocardiogram (ECG) at the time of their admission to hospital is associated with larger final infarct size and greater mortality. This study assessed the results of emergency coronary angioplasty in patients with anterior acute myocardial infarction with and without distortion of the terminal portion of the QRS complex on the admission ECG.

METHODS

We assessed the Thrombolysis in Myocardial Infarction (TIMI) trial flow grade, resolution of ischemic ECG changes, and clinical outcome after emergency angioplasty for acute anterior wall myocardial infarction in patients with (n = 21) and without (n = 21) distortion of the terminal portion of the QRS complex on the admission ECG.

RESULTS

Compared with patients without distortion of the terminal portion of the QRS complex on the admission ECG, those with distortion had a significantly lower incidence of TIMI flow grade 3 (52% compared with 84%, P < 0.05), lower rate of resolution of the ischemic ECG changes (33% compared with 84%, P < 0.005), and greater rate of mortality during their stay in hospital despite successful balloon angioplasty (19% compared with 0%, P < 0.05).

CONCLUSIONS

In patients with anterior wall acute myocardial infarction, distortion of the terminal portion of the QRS complex on the admission ECG predicts a greater mortality rate and a greater incidence of reflow impairment after emergency angioplasty.

Admission clinical and electrocardiographic characteristics predicting an increased risk for early reinfarction after thrombolytic therapy

BACKGROUND

This study assessed the ability of clinical and electrocardiographic variables routinely obtained on admission to identify patients with acute myocardial infarction treated with thrombolytic therapy at risk of early reinfarction.

METHODS AND RESULTS

The study included 2602 patients who received thrombolytic therapy for acute myocardial infarction. Baseline demographic variables and admission clinical and electrocardiographic variables were compared between patients with and without reinfarction. Multivariable logistic regression technique was used and included recurrent infarction as the dependent variable, and baseline demographic, clinical, and electrocardiographic variables as independent variables. History of hypertension (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.00 to 2.31) and diabetes mellitus (OR 1.59, 95% CI 1.00 to 2.53) were associated with a higher risk, and current smoking was associated with a lower risk (OR [no versus yes] 1.64, 95% CI 1.05 to 2.58) of early hospital reinfarction. Distortion of the terminal portion of the QRS complex (OR 1.86, 95% CI 1.20 to 2.87) and absence of abnormal Q waves on admission (OR 1.54, 95% CI 0.98 to 2.43) were associated with increased risk of early reinfarction.

CONCLUSIONS

A simple electrocardiographic sign is a reliable predictor of early reinfarction among patients who receive thrombolytic therapy for acute myocardial infarction.

Adding the new calcium antagonist mibefradil to patients receiving long-term beta-blocker therapy results in improved antianginal and antiischemic efficacy

OBJECTIVE

The objective of this study was to evaluate the efficacy, tolerability, and safety of mibefradil, a new selective T-type calcium channel blocker, in patients with chronic stable angina pectoris receiving concomitant beta-blocker therapy.

DESIGN

This was a multicenter, double-blind, placebo-controlled study.

METHODS

Ninety-five patients receiving a stable dose of beta-blockers, which was not changed for the purpose of the study, were administered either 50 mg mibefradil once daily for 2 weeks, then 100 mg once daily for 2 weeks, or matching placebo. Efficacy was evaluated by treadmill exercise tolerance testing 24 hours after dose and by diary registration of anginal episodes and nitroglycerin consumption.

RESULTS

Two weeks of treatment with 50 mg mibefradil resulted in a significant increase in symptom-limited exercise duration and a significant delay in the onset of persistent 1 mm ST-segment depression (placebo-corrected treatment effect: 23.2 and 51.7 seconds, respectively). Treatment with the 100 mg dose for 2 additional weeks resulted in a larger improvement in treadmill exercise tolerance testing duration and onset of ischemia (placebo-corrected treatment effect: 52.7 and 75.8 seconds, respectively). In addition, a significant decrease in weekly anginal episodes was observed with the 100 mg dose of mibefradil compared with the effect in the placebo group (-53% vs - 12%, p = 0.037).

CONCLUSIONS

The combined treatment of mibefradil and beta-blockers was well tolerated, and the overall incidence of adverse events was no different from that with beta-blockers alone. The results indicate that adding mibefradil to chronic beta-blocker treatment is associated with significant improvement in efficacy, which is not achieved at the expense of tolerability.

Comparison of patients with inferior wall acute myocardial infarction with versus without ST-segment elevation in leads V5 and V6

One hundred forty-one patients with first acute inferior wall myocardial infarction were examined. ST-segment elevation in precordial leads V5 to V6 was found in 34; 94% of them had "mega-artery" compared with 2% in those without ST-segment elevation in precordial leads V5 to V6.

New electrocardiographic criteria for predicting either the right or left circumflex artery as the culprit coronary artery in inferior wall acute myocardial infarction

Two readily obtainable measurements on the admission electrocardiogram-a higher ST-segment elevation in lead III than in lead II and a greater ST-segment depression in lead aVL than in lead I-can distinguish right coronary artery from left circumflex artery-related acute inferior wall myocardial infarction.

Admission clinical and electrocardiographic characteristics predicting in-hospital development of high-degree atrioventricular block in inferior wall acute myocardial infarction

This study assessed the ability of simple clinical and electrocardiographic variables routinely obtained on admission to identify patients who are at high risk of developing high-degree atrioventricular (AV) block during hospitalization in 1,336 patients with inferior wall acute myocardial infarction (AMI). Patients were classified into 2 initial electrocardiographic patterns based on the J-point to R-wave amplitude ratio: pattern 1: those with J point/R wave <0.5 and pattern 2: patients with J point/R wave > or =0.5 in > or =2 leads of the inferior leads II, III, and aVF. High-degree AV block was found in 6.7% of patients (41 of 615) with pattern 1 versus 11.8% of the patients (85 of 721) with pattern 2 on admission electrocardiogram (p = 0.0008). Multivariate logistic regression analysis revealed that the only variables found to be independently associated with high-degree AV block were female gender (odds ratio [OR] 1.48; 95% confidence interval [CI] 0.98 to 2.23; p = 0.06); Killip class on admission > or =2 (OR 2.24; CI 1.43 to 3.51; p = 0.0004); initial electrocardiographic pattern 2 versus pattern 1 (OR 1.82; CI 1.22 to 2.21; p = 0.003); and absence of abnormal Q waves on admission (OR yes vs no 0.68; CI 0.44 to 1.05; p = 0.08). A simple electrocardiographic sign (J point/R wave > or =0.5 in > or =2 leads) is a reliable predictor of the development of advanced AV block among patients receiving thrombolytic therapy for inferior wall AMI.

Coronary wallstent implantation by the transradial artery approach. A case report

The authors report the implantation of two wallstents in a patient by use of the transradial artery approach. This approach for coronary wallstent implantation allows for intensive anticoagulation therapy with less risk of bleeding.

Pathophysiology of precordial ST-segment depression in inferior wall acute myocardial infarction: an echocardiographic appraisal

Precordial ST-segment depression (PSD) in inferior wall acute myocardial infarction (IAMI), especially when maximal in leads V4-V6, has been shown to portend a higher rate of heart failure and mortality. To better understand the pathophysiology behind this phenomenon, we evaluated patients with a first IAMI by echocardiography 48-72 h after the acute event, using segmental scoring (0 = normal to 3 = dyskinesia) of left ventricle wall motion, and a dichotomous assessment of right ventricle involvement. Patients were categorized into 3 groups: I = no PSD (n = 14); II = maximal PSD in leads V1-V3 (n = 28); III = maximal PSD in leads V4-V6 (n = 8). As compared with group I, patients in groups II-III had more severe wall motion abnormalities in inferior segments (1.36 +/- 0.97 vs. 2.19 +/- 1.74, p = 0.04), and a similar trend for posterior and lateral segments (1 +/- 1.75 vs. 2 +/- 2.41, p = 0.11), translating into a worse total left ventricle score (2.36 +/- 2.34 vs. 4.25 +/- 4.05, p < 0.05). Frequency of right ventricle involvement was similar in patients with and without PSD (6 (43%) vs. 9 (25%), p = 0.37). Segmental scores for groups I, II, and III, respectively, were not different for inferior (1.36 +/- 1, 2.25 +/- 1.82 and 2 +/- 1.51, p = 0.24), posterior and lateral (1 +/- 1.75, 1.96 +/- 2.32 and 2.13 +/- 2.9, p = 0.38), and septal, anteroseptal and anterior segments (0 +/- 0, 0.04 +/- 0.19 and 0.13 +/- 0.35, p = 0.28). Right ventricle abnormalities occurred in 43, 21 and 38% of patients in groups I, II and III, respectively, p = 0.3. Thus, IAMI with PSD is associated with worse left ventricle wall motion. However, since patients with maximal PSD in leads V4-V6 do not have greater wall motion abnormalities or higher rate of right ventricle involvement, their poorer prognosis cannot be explained by worse systolic dysfunction. We propose that maximal PSD in leads V4-V6 reflects transient diffuse ischemia and altered diastolic distensibility due to extensive coronary artery disease, causing increased left ventricle end-diastolic pressure.

Serum basic fibroblast growth factor levels in patients with ischemic heart disease

BACKGROUND

Being a potent promoter of endothelial and smooth muscle cell proliferation, basic fibroblast growth factor (bFGF) is presumed to play a key role in coronary collateral development and atherogenesis.

PURPOSE

To characterize serum bFGF levels in patients with ischemic heart disease.

METHODS

The study population consisted of patients with angina (n=33) and after uncomplicated myocardial infarction (n=12). The number of significantly stenosed (> or = 50%) vessels and angiographic coronary collateral score were noted. Blood was drawn immediately prior to elective coronary angiography in study patients for bFGF levels. Twenty healthy, age-matched subjects served as control for serum bFGF.

RESULTS

Serum bFGF levels were undetectable in all 20 control subjects, but were detectable in 15/33 (45%) patients with angina and 3/12 (25%) post-infarction patients, respectively (P=0.002). Serum bFGF levels were detectable in 13/23 (57%) patients with 0- or 1-vessel disease, as compared with 5/22 (23%) patients with 2- or 3-vessel disease (P<0.05). Detectable serum bFGF levels were not in correlation with coronary collateral score (P=1).

CONCLUSIONS

Serum levels of bFGF are elevated in patients with ischemic heart disease, particularly in those with minimal coronary artery disease. We postulate that detectable serum bFGF levels reflect active atherogenesis rather than myocardial collateral development.

Importance of left anterior hemiblock development in inferior wall acute myocardial infarction

Of the 87 consecutive patients admitted with first inferior wall acute myocardial infarction, 17 had acute left anterior hemiblock. The appearance of left anterior hemiblock identified a specific group with more extensive coronary artery disease and suggests disease of the left anterior descending coronary artery.

Importance of the conal branch of the right coronary artery in patients with acute anterior wall myocardial infarction: electrocardiographic and angiographic correlation

OBJECTIVES

This study assessed prospectively the correlation between the conal branch of the right coronary artery and the pattern of ST segment elevation in leads V1 and V3R during anterior wall acute myocardial infarction (AMI).

BACKGROUND

The traditional electrocardiographic (ECG) definition of anteroseptal AMI-ST segment elevation in leads V1 to V3-has recently been challenged. The significance of ST segment elevation in lead V1 during anterior wall AMI is unclear.

METHODS

The admission 12-lead ECG with additional lead V3R and the coronary angiograms performed within 10 days of hospital admission were evaluated in 28 consecutive patients (mean age +/- SD 62 +/- 9 years) admitted to the coronary care unit with anterior wall AMI. Patients were classified into two groups according to the magnitude of ST segment elevation in lead V1: group A (elevation > or = 1.5 mm, n = 12) and group B (elevation < 1.5 mm, n = 16). Two types of conal branch were identified: small (not reaching the interventricular septum [IVS]) and large (reaching the IVS).

RESULTS

ST segment elevation in lead V3R was found in 11 (92%) and 6 (37%) patients from group A and group B, respectively (p < 0.001); a small conal branch was seen in 10 (83%) and 3 (19%) patients, respectively (p < 0.001). Ten patients (all from group B) had a large conal branch.

CONCLUSIONS

ST segment elevation in lead V1 in the admission ECG of patients with anterior wall AMI is strongly related to ST segment elevation in lead V3R and is associated with a small conal branch. Our findings suggest that lead V1 reflects the right paraseptal area supplied by the septal branches of the left anterior descending coronary artery (LAD), alone or together with the conal branch. The absence of ST segment elevation in lead V1 during anterior AMI suggests that the IVS is protected by a large conal branch in addition to the septal branches of the LAD (double circulation).

The relationship between the electrocardiographic pattern with TIMI flow class and ejection fraction in patients with a first acute anterior wall myocardial infarction

AIMS

The aim of this study was to assess the value of the electrocardiogram in predicting the patency of the left anterior descending artery and left ventricular ejection fraction in patients with a first acute anterior wall myocardial infarction at discharge from the coronary care unit.

METHOD

We included 116 consecutive patients with an acute anterior myocardial infarction who had undergone coronary angiography and left ventriculography before discharge from the coronary care unit (7th to 10th day). The ST segment, either elevated or isoelectric (< 1 mm), and the T wave (positive or negative) in precordial leads V2-V4 were analysed and compared to the TIMI flow from each patient.

RESULTS

Out of 69 patients with negative T waves, 38 (55%) had TIMI flow 3 compared with 20 (29%) and 11 (16%) with TIMI flow 2 and 0-1, respectively; and out of 47 patients with positive T waves seven (15%) had TIMI flow 3, 17 (36%) TIMI flow 2 and 23 (49%) TIMI flow 0-1 (P < 0.001). Out of 63 patients with an isoelectric ST segment, 35 (55%) had TIMI flow 3, 18 (29%) TIMI flow 2 and 10 (16%) TIMI flow 0-1, and out of 53 with ST segment elevation, 10 (19%) had TIMI flow 3, 19 (36%) TIMI flow 2 and 24 (45%) TIMI flow 0-1 (P < 0.001). When both parameters were analysed together, we found that in 46 patients with both isoelectric ST segments and negative T waves, 30 (65%) had TIMI flow 3 compared with two of 30 (7%) patients with ST segment elevation and positive T waves (P < 0.001). Patients with isoelectric ST segments had a better degree of left ventricular ejection fraction (57.8 +/- 14.1%) than patients with ST segment elevation (41.7 +/- 13%) (P < 0.001). Patients with positive and negative T waves had a similar left ventricular ejection fraction (49 +/- 18.1% vs 51 +/- 14%).

CONCLUSION

We concluded that patients with a first acute anterior myocardial infarction and an electrocardiogram pattern of an isoelectric ST segment and a negative T wave have a higher incidence of a patent left anterior descending coronary artery than similar patients with ST segment elevation and a positive T wave. An isoelectric ST segment is also related to better left ventricular function.

Radiofrequency catheter ablation of ectopic atrial tachycardia

Ectopic atrial tachycardia (EAT) is an uncommon type of supraventricular tachycardia. It is usually chronic, incessant and resistant to pharmacologic therapy. Radiofrequency catheter ablation, which has become one of the treatments of choice for the more common types of supraventricular tachycardia, has recently also been shown to be effective in EAT. Radiofrequency catheter ablation was attempted in three patients with incessant EAT. Two of the patients, aged 7 and 13 years, had signs of left ventricular dysfunction, and the EAT originated in the left atrium. The remaining patient, aged 72 years, had a right EAT with normal left ventricular function. Radiofrequency ablation was guided by endocardial atrial mapping to locate the site of earliest atrial activation. Ablation was successful in all three patients, with complete cure of the tachycardia for a follow-up period of 12 to 19 months. Radiofrequency catheter ablation of EAT is highly successful and should be considered as one of the treatments of choice for this arrhythmia.

Maximal precordial ST-segment depression in leads V4-V6 in patients with inferior wall acute myocardial infarction indicates coronary artery disease involving the left anterior descending coronary artery system

BACKGROUND

In inferior wall acute myocardial infarction, maximal ST-segment depression in left precordial leads (V4-V6) has been shown to be associated with increased in-hospital mortality, presumably due to coronary artery disease involving the left anterior descending coronary artery system.

METHODS

We measured ST-segment deviation from baseline in the initial electrocardiogram of patients with inferior wall acute myocardial infarction, who subsequently underwent coronary angiography during their in-hospital stay. Patients were divided into three groups: (I) No precordial ST-segment depression (n = 34). (II) Maximal precordial ST-segment depression in leads V1-V3 (n = 44). (III) Maximal precordial ST-segment depression in leads V4-V6 (n = 14).

RESULTS

The left anterior descending coronary artery or its diagonal branch were stenosed (> 50%) in 32%, 41%, and 71% of patients in groups I, II, and III, respectively (p = 0.04), and severely stenosed (> 70%) in 18%, 18% and 57% of patients in the respective groups (p = 0.007).

CONCLUSION

In patients with inferior wall acute myocardial infarction, maximal precordial ST-segment depression in leads V4-V6 is suggestive of severe coronary artery disease involving the left anterior descending coronary artery or its diagonal branch.

The effect of the ingestion of ethanol on obstruction of the left ventricular outflow tract in hypertrophic cardiomyopathy

BACKGROUND

Ethanol causes vasodilation, which might have an adverse effect, due to increased obstruction of the left ventricular outflow tract, in patients with hypertrophic obstructive cardiomyopathy. We assessed the hemodynamic effects of the ingestion of ethanol, in an amount commonly consumed socially, in patients with hypertrophic cardiomyopathy.

METHODS

We performed echocardiography in 36 patients before and several times after the ingestion of either 50 ml of 40 percent ethanol or an isocaloric placebo with the aroma of rum. Each patient received both ethanol and placebo, on different days. The patients, but not the physicians, were blinded to the content of the drink. We measured the sizes of the left atrium and left ventricle, the left-ventricular-wall thickness, blood pressure, heart rate, the degree of systolic anterior motion of the mitral valve, and the pressure gradient across the left ventricular outflow tract.

RESULTS

The ingestion of ethanol regulated in a significant drop in the mean (+/- SD) systolic blood pressure (from 130.5 +/- 18.6 to 122.5 +/- 20.3 mm Hg, P<0.001), a significant increase in systolic anterior motion of the mitral valve (from a grade of 2.1 to a grade of 2.5, P<0.001), and a 63 percent increase in the mean gradient across the left ventricular outflow tract (from 38.1 +/- 26.5 to 62.2 +/- 42.4 mm Hg, P<0.001). These changes, which were not associated with symptoms, did not occur after the ingestion of placebo.

CONCLUSION

The ingestion of a small amount of ethanol caused an increase in the gradient across the left ventricular outflow tract in patients with hypertrophic obstructive cardiomyopathy, which could have and adverse clinical effect.

Distortion of the terminal portion of the QRS on the admission electrocardiogram in acute myocardial infarction and correlation with infarct size and long-term prognosis (Thrombolysis in Myocardial Infarction 4 Trial)

Previous studies have shown an association between distortion of the terminal portion of the QRS (QRS[+] pattern: emergence of the J point > or = 50%. of the R wave in leads with qR configuration or disappearance of the S wave in leads with an Rs configuration) on admission and in-hospital mortality in acute myocardial infarction (AMI). However, the mechanism for this association is not known. We assessed the relation between QRS(+) pattern and coronary angiographic findings, infarct size, and long-term prognosis in the Thrombolysis In Myocardial Infarction 4 trial. Patients were allocated into 2 groups based on the presence (QRS[+], n = 85) or absence (QRS[-], n = 293) of QRS distortion. The QRS(+) patients were older (mean +/- SD: 61.1 +/- 10.6 vs 57.5 +/- 10.6 years, p = 0.004), had more anterior AMI (49% vs 37%, p = 0.04), and less previous angina (42% vs 54%, p = 0.05). QRS(+) patients had larger infarct size as assessed by creatine kinase release over 24 hours (209 +/- 147 vs 155 +/- 129, p = 0.003), and predischarge sestamibi (MIBI) defect (17.9 +/- 15.9% vs 11.2 +/- 13.4%, p <0.001). When adjusting for difference in baseline characteristics, p values for the differences in 24-hour creatine kinase release were 0.03 and 0.64 for anterior and nonanterior AMI, respectively, and for MIBI defect size 0.03 and 0.02, respectively. One-year mortality (18% vs 6%, p = 0.03) was higher and the weighted end point of death, reinfarction, heart failure, or left ventricular ejection fraction <40% (0.33 +/- 0.37 vs 0.24 +/- 0.32, p = 0. 13), tended to be higher in the anterior AMI patients with QRS(+). No difference in clinical outcome was found in patients with non-anterior AMI. These findings suggest that this simple electrocardiographic definition of presence of QRS(+) pattern on admission may provide an early estimation of infarct size and long-term prognosis, especially in anterior AMI.

Is the heart a source for elevated circulating endothelin levels during aorta-coronary artery bypass grafting surgery in human beings?

Reports have shown increased systemic levels of endothelins during coronary artery bypass grafting in human beings. It was not known whether increased endothelin levels during coronary artery bypass grafting reflect a general systemic response to the surgical procedure or increased myocardial production of endothelins in response to ischemia and reperfusion. We therefore measured endothelin levels in the right atrium and proximal aorta of 15 patients undergoing coronary artery bypass grafting for anginal syndrome immediately before aortic crossclamping and again after cessation of cardiopulmonary bypass. In five patients, we also measured coronary sinus levels of endothelins during cardiopulmonary bypass circulation. We found that endothelin levels were elevated throughout the surgical procedure. Right atrial endothelin levels were significantly elevated after cessation of cardiopulmonary bypass circulation with respect to values immediately before aortic crossclamping (11.1 +/- 3.1 vs 14.2 +/- 3.7 pg/ml, p = 0.008), whereas endothelin levels in the proximal aorta did not rise significantly (10.5 +/- 2.3 vs 11.6 +/- 2.4 pg/ml, p > 0.5). Coronary sinus endothelin levels tended to decline temporarily during cardiopulmonary bypass circulation (11.1 +/- 2.1 pg/ml before aortic crossclamping, 7.9 +/- 1.9 1 minute after release of aortic crossclamp, and 9.9 +/- 2.1 pg/ml after release of partial aortic crossclamping, p = 0.06). We conclude that the rise in right atrial endothelin levels during coronary artery bypass grafting reflects systemic production and secretion of endothelins, probably by vasculature or organs distal to the proximal aorta, and is not the result of increased myocardial production and secretion of endothelins.

Prognostic significance of precordial ST segment depression on admission electrocardiogram in patients with inferior wall myocardial infarction

OBJECTIVES

This study assessed retrospectively the correlation between the pattern of precordial ST segment depression on the admission electrocardiogram (ECG) and hospital mortality in patients with an inferior myocardial infarction treated with intravenous thrombolytic therapy.

BACKGROUND

Previous studies have shown that in acute inferior myocardial infarction, ST segment depression in the precordial leads is associated with increased hospital mortality. However, the significance of the different patterns of precordial ST segment depression has been evaluated in only two previous studies.

METHODS

The study included 1,321 patients (1,020 men) who enrolled in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO-I) trial in Israel and received intravenous thrombolytic therapy. Patients with an ST segment elevation > or = 0.1 mV in at least two of the inferior leads were included. Patients were classified into four groups on the basis of their admission ECG: group I = patients with no precordial ST segment depression (n = 346); group II = those for whom the sum of ST segment depression in leads V1 to V3 was greater than that in leads V4 to V6 (n = 700); group III = those for whom the sum of ST depression in leads V1 to V3 was equal to that in leads V4 to V6 (n = 162); group IV = those with maximal ST depression in leads V4 to V6 (n = 113).

RESULTS

The overall hospital mortality rate was 3.6% (48 patients): for groups I, II, III and IV it was 2.9%, 2.8%, 4.3% and 9.7%, respectively. Multivariable logistic regression analysis confirmed that hospital mortality was independently associated with the pattern of precordial ST segment depression. The odd ratios in group IV relative to group I was 2.78 (95% confidence interval 1.26 to 6.13, p = 0.007).

CONCLUSIONS

The risk of mortality is higher in patients with an inferior myocardial infarction and maximal ST segment depression in precordial leads V4 to V6 versus precordial leads V1 to V3 on the admission ECG.

Relationship between late potentials and the predischarge electrocardiographic pattern in patients with acute anterior wall myocardial infarction

HYPOTHESIS

The presence of late potentials on the signal-averaged electrocardiogram (SAECG) identifies patients at high risk for development of ventricular tachyarrhythmias after myocardial infarction (MI).

METHODS

The electrocardiogram and left ventricular function in 65 patients recovering from a first acute anterior wall MI were analyzed. We compared the pattern of the ST segment (isoelectric or elevated) and of the T wave (positive or negative) with the SAECG using an orthogonal bipolar lead configuration (X, Y, Z) with bidirectional Butterworth filtering (Simson's method).

RESULTS

Abnormal SAECG was found in 17 (26%) patients; 11 of 18 patients with ST elevation had abnormal SAECG, and only 6 of 47 patients with isoelectric ST segment developed abnormal SAECG (p < 0.0001, odds ratio = 10.74). Of 19 patients with positive T waves, 10 had abnormal SAECG, and abnormal SAECG was found in 7 of 46 patients with negative T waves (p < 0.003, odds ratio = 5.27). When both parameters were considered together, 9 of 12 patients with ST elevation and positive T wave developed abnormal SAECG, and 35 of 40 patients with isoelectric ST and negative T wave had normal SAECG (p < 0.0002). Left ventricular ejection fraction was similar in patients with abnormal SAECG (43 +/- 14%) and normal SAECG (46 +/- 11%).

CONCLUSION

These findings suggest that patients with anterior wall MI and a predischarge pattern of ST elevation and positive T wave have a higher incidence of abnormal SAECG and therefore may have a worse prognosis, especially related to the subsequent development of ventricular arrhythmias.

Prominent atrial wave and diastasis deflection in the radionuclide diastolic volume curve during exercise--sensitive marker for coronary artery disease

It is well-known that many patients with coronary artery disease have reduced left ventricular diastolic distensibility with normal systolic function. However, researchers have to data focused on the diastolic rapid filling phase of the radionuclide volume curve in ischemic patients, paying less attention to the ensuing left ventricular filling associated with passive filling ('diastasis') and atrial contraction ('A' wave). We analyzed the radionuclide volume curves of 27 consecutive patients suspected ischemic heart disease, who manifested normal systolic function at rest and during exercise, as assessed by multigated equilibrium technetium-99m radionuclide cineangiography. For all patients, the amplitude of the maximal 'A' deflection relative to the peak of the diastolic curve (presented as percentage units) was calculated manually from the radionuclide left ventricular volume curves obtained at rest and during exercise. Twenty patients (Group I) had transient perfusion defects on thallium scintigraphy (treadmill), and 7 (Group II) did not. Patients in Group I manifested prominent 'A'-deflections during exercise, with a rise of 120 +/- 43% (mean +/- S.D.) from rest to exercise, whereas the patients in Group 11 had only 34 +/- 11% (mean +/- S.D.) rise in 'A' wave amplitude during exercise (P = 0.0001). We conclude that the appearance of a prominent 'A' deflection in the radionuclide left ventricular volume curve during exercise might be a sensitive marker of myocardial ischemia.