Juan L. Delcán

Randomized comparison of coronary stent implantation and balloon angioplasty in the treatment of de novo coronary artery lesions (START): a four-year follow-up.

OBJECTIVE The purpose of this study was to test the hypothesis that stent implantation in de novo coronary artery lesions would result in lower restenosis rates and better long-term clinical outcomes than balloon angioplasty. BACKGROUND Placement of an intracoronary stent, as compared with balloon angioplasty, has proven to reduce the rate of restenosis. However, the long-term clinical benefit of stenting over angioplasty has not been assessed in large randomized trials. METHODS We randomly assigned 452 patients with either stable (129 patients) or unstable (323 patients) angina pectoris to elective stent implantation (229 patients) or standard balloon angioplasty (223 patients). Coronary angiography was performed at baseline, immediately after the procedure and six months later. End points were the rate of restenosis at six months and a composite of death, myocardial infarction (MI) and target vessel revascularization over four years of follow-up. RESULTS Procedural success rate was achieved in 84% and 95% (balloon angioplasty vs. stent, respectively). The increase in the minimal luminal diameter was greater in the stent group both after the intervention (2.02 +/- 0.6 mm vs. 1.43 +/- 0.6 mm in the angioplasty group; p < 0.0001), and at six-month follow-up (1.98 +/- 0.7 mm vs. 1.63 +/- 0.7 mm; p < 0.001). The corresponding restenosis rates were 22% and 37%, respectively (p < 0.002). After four years, no differences in mortality (2.7% vs. 2.4%) and nonfatal MI (2.2% vs. 2.8%) were found between the stent and the angioplasty groups, respectively. However, the requirement for further revascularization procedures of the target lesions was significantly reduced in the stent group (12% vs. 25% in the angioplasty group; relative risk 0.49, 95% confidence interval 0.32 to 0.75, p = 0.0006); most of the repeat procedures (84%) were carried out within six months of entry into the study. CONCLUSIONS Patients who received an intracoronary stent showed a lower rate of restenosis than those treated with conventional balloon angioplasty. The benefit of stenting was maintained four years after implantation, as manifested by a significant reduction in the need for repeat revascularization.

Left atrial appendage doppler flow patterns: Implications on thrombus formation

The characteristics and clinical implications of left atrial appendage (LAA) flow have not been clearly analyzed. Thirty-nine consecutive patients underwent a transesophageal echocardiographic (TEE) color Doppler study to correlate the LAA pulsed Doppler flow pattern with echocardiographic variables and the cardiac rhythm of each patient. Three different LAA flow patterns were identified. Type I flow, characterized by a biphasic pattern (waves of filling and emptying), was found in 17 patients, all in sinus rhythm; it was not associated with LAA spontaneous contrast or thrombus. Mean peak velocities of the filling and emptying waves were, respectively: 28 +/- 12 cm/sec and 31 +/- 9 cm/sec. Type II sawtooth active flow (eight patients) (mean peak velocity: 49 +/- 12 cm/sec) was only detected in atrial fibrillation (AF) and dilated LAA (LAA area: 421 +/- 40 mm2) but without thrombus or significant LAA spontaneous echocardiographic contrast. Type III flow pattern was noted in 14 patients with AF and a very dilated LAA (LAA area: 619 +/- 96 mm2). This flow pattern was characterized by the absence of identifiable flow waves and was associated with the presence of LAA spontaneous contrast; the majority (six of seven) had evidence of thrombus. We concluded that the LAA is a dynamic structure in which TEE study identified three flow patterns with different implications. AF is associated with two LAA flow types (II and III) with a larger LAA size as well as a higher incidence of LAA clots in type III flow.

Primary angioplasty versus systemic thrombolysis in anterior myocardial infarction.

OBJECTIVES This study compares the efficacy of primary angioplasty and systemic thrombolysis with t-PA in reducing the in-hospital mortality of patients with anterior AMI. BACKGROUND Controversy still exists about the relative benefit of primary angioplasty over thrombolysis as treatment for AMI. METHODS Two-hundred and twenty patients with anterior AMI were randomly assigned in our institution to primary angioplasty (109 patients) or systemic thrombolysis with accelerated t-PA (111 patients) within the first five hours from the onset of symptoms. RESULTS Baseline characteristics were similar in both groups. Primary angioplasty was independently associated with a lower in-hospital mortality (2.8% vs. 10.8%, p = 0.02, adjusted odds ratio 0.23, 95% confidence interval 0.06 to 0.85). During hospitalization, patients treated by angioplasty had a lower frequency of postinfarction angina or positive stress test (11.9% vs. 25.2%, p = 0.01) and less frequently underwent percutaneous or surgical revascularization after the initial treatment (22.0% vs. 47.7%, p < 0.001) than did patients treated by t-PA. At six month follow-up, patients treated by angioplasty had a lower cumulative rate of death (4.6% vs. 11.7%, p = 0.05) and revascularization (31.2% vs. 55.9%, p < 0.001) than those treated by t-PA. CONCLUSIONS In centers with an experienced and readily available interventional team, primary angioplasty is superior to t-PA for the treatment of anterior AMI.

Influence of Sex on the Short-term Outcome of Elderly Patients With a First Acute Myocardial Infarction

BACKGROUND Sex seems to affect the course of acute myocardial infarction (AMI) in the general population. Although the epidemiological importance of female sex among patients with AMI is more important from the sixth decade of life, little is known about the impact of sex on the outcome of AMI in the elderly. METHODS AND RESULTS To determine the differences between sexes in the outcome of AMI in the elderly, we compared the clinical history and evolution of 204 consecutive patients (99 men, 105 women) > or = 75 years of age admitted with a first AMI. Women had a higher prevalence (P < .01) of hypertension (60% versus 32%) and diabetes (41% versus 18%), whereas men were more frequently smokers (41% versus 4%, P < .0001); these factors were associated with higher rates of congestive heart failure. Women showed lower ejection fractions and higher rates of congestive heart failure (odds ratio [OR], 2.32; 95% CI, 1.32 to 4.12) and shock (OR, 2.78; 95% CI, 1.29 to 6.40). Mortality rate was higher in women (40% versus 23%, P = .01; OR, 2.29; 95% CI, 1.26 to 4.26); however, sex was excluded as an independent predictor of in-hospital mortality in every regression model tested (OR, 0.75; 95% CI, 0.25 to 2.21). CONCLUSIONS After a first AMI, elderly women experience a more complicated hospital course than men. The increase in mortality risk seems to be related to the impact of cardiovascular risk factors on left ventricular function more than to sex itself.

In-Hospital Outcome of Elderly Patients With Acute Inferior Myocardial Infarction and Right Ventricular Involvement

BACKGROUND There are some specific high-risk subgroups of patients with acute inferior myocardial infarction, such as older patients and those with right ventricular involvement. However, the clinical implications of right ventricular infarction in elderly subjects have not been studied previously. METHODS AND RESULTS To determine the clinical impact of right ventricular involvement in elderly patients with inferior myocardial infarction, we studied the in-hospital outcome of 198 consecutive patients > or = 75 years of age with a first acute inferior myocardial infarction according to the presence of ECG or echocardiographic criteria of right ventricular infarction. In patients with right ventricular involvement (41%), in-hospital case fatality rate was 47% (mainly because of nonreversible low cardiac output cardiogenic shock) compared with 10% in patients without right ventricular involvement (P<.001). Patients with right ventricular involvement also had a significantly higher incidence of cardiogenic shock (32% versus 5%), which was independent of left ventricular ejection fraction, complete AV block (33% versus 9%), and interventricular septal rupture (9% versus 0%). After adjustment for age, sex, diabetes, shock on admission, left ventricular systolic dysfunction, and complete AV block, right ventricular infarction remained a powerful independent predictor of in-hospital death (adjusted odds ratio, 4.0; 95% confidence interval, 1.3 to 14.2). CONCLUSIONS Elderly patients with acute inferior myocardial infarction have a substantially increased risk of death during hospitalization when right ventricular involvement is present. The poorer outcome is due mainly to the high incidence of cardiogenic shock and its infrequent reversibility.

Effects of dobutamine on doppler echocardiographic indexes of aortic stenosis

OBJECTIVES This study sought to assess the diagnostic implications of the flow dependence of Doppler echocardiographic indexes of aortic valve stenosis. BACKGROUND Although valve area has been shown to change with alterations in flow rate, the diagnostic consequences of this phenomenon remain unknown. Valve resistance has been suggested as a more stable index for evaluating aortic stenosis. METHODS A low dose dobutamine protocol was performed in 35 patients with aortic stenosis. Hemodynamic indexes were obtained by Doppler echocardiography at baseline and at each dobutamine dose. RESULTS As a result of the shortening of the systolic ejection period, flow increased from (mean +/- SD) 164 +/- 48 to 229 +/- 102 ml/s (p < 0.0001). At peak flow, valve area increased by 28% (from 0.5 +/- 0.2 to 0.6 +/- 0.3 cm2, p < 0.0001), whereas valve resistance decreased by 4% (from 498 +/- 252 to 459 +/- 222 dynes.s.cm-5, p = 0.04). This observed change in resistance was smaller than that for valve area (p < 0.01). The flow dependence of valve area varied among individual patients (p < 0.0001). Multivariate analysis identified calcific degenerative etiology (beta 0.29, p = 0.002), left ventricular velocity of fiber shortening (beta 0.22, p = 0.01), baseline flow (beta -0.28, p = 0.04) and amount of flow increased induced by dobutamine (beta 0.90, p < 0.0001) as factors related to valve area flow dependence. CONCLUSIONS Although all Doppler echocardiographic indexes of aortic stenosis are affected by flow, valve resistance is more stable than valve area under dobutamine-induced hemodynamic changes. Baseline valve area may be unreliable in patients with calcific degenerative aortic stenosis and low output states.

Dissection of the aortic sinus of valsalva complicating coronary catheterization: Cause, mechanism, evolution, and management

We have rarely observed the appearance of a dissection of the aortic sinus of Valsalva during catheterizations of the related coronary artery. The aim of this study is to describe the cause, mechanism, and evolution of this complication, which have implications for the management of the patient. According to our experience (one case out of 12,546 diagnostic and three cases out of 4,970 angioplasty procedures performed during the last 6 years), the dissection of the sinus of Valsalva always results from the retrograde extension of a dissection of the right coronary artery. It usually remains localized, but it may quickly involve the entire aorta. Contrast injections and balloon inflations promote its propagation, so these procedures should be avoided if possible. Instead of angiography, transesophageal echocardiogram is a safe and accurate method for studying its extension and as a follow-up method. The sinus of Valsalva dissections that remain localized during catheterization tend to spontaneously resolve in the first month.

Influence of Collateral Circulation on In-Hospital Death From Anterior Acute Myocardial Infarction

OBJECTIVES Our purpose was to study whether the in-hospital prognosis of anterior acute myocardial infarction (AMI) is influenced by preexistent collateral circulation to the infarct-related artery. BACKGROUND Collateral circulation exerts beneficial influences on the clinical course after AMI, but demonstration of improved survival is lacking. METHODS We studied 238 consecutive patients with anterior AMI treated by primary angioplasty within the first 6 h of the onset of symptoms. Fifty-eight patients with basal Thrombolysis in Myocardial Infarction (TIMI) flow >1 in the infarct-related artery or with inadequate documentation of collateral circulation were excluded. Collateral channels to the infarct-related artery before angioplasty were angiographically assessed, establishing two groups: 115 patients (64%) without collateral vessels (group A) and 65 patients (36%) with collateral vessels (group B). RESULTS There were no differences in baseline characteristics between groups A and B, except for the greater prevalence of previous angina in group B (15% vs. 34%, p = 0.003). During the hospital stay, 26 patients (23%) in group A and 5 (8%) in group B died (p = 0.01). Cardiogenic shock accounted for 74% of deaths. Cardiogenic shock developed in 30 patients (26%) in group A and in 4 (6%) in group B (p = 0.001). The absence of collateral circulation appeared to be an independent predictor of in-hospital death (odds ratio 3.4, 95% confidence interval 1.2 to 9.6, p = 0.02) and cardiogenic shock (odds ratio 5.6, 95% confidence interval 1.9 to 17, p = 0.002). CONCLUSIONS Preexistent collateral circulation decreases in-hospital death from anterior AMI by reducing the incidence of cardiogenic shock.

Predictors of left atrial spontaneous echo contrast and thrombi in patients with mitral stenosis and atrial fibrillation

The purpose of this study was to investigate the independent factors associated with the presence of left atrial (LA) spontaneous echo contrast (SEC) and thromboembolic events in patients with mitral stenosis (MS) in chronic atrial fibrillation (AF). Factors independently associated with LASEC, thrombi, and embolic events have been mainly investigated in patients with nonvalvular AF or inhomogeneous populations with rheumatic heart disease. Transesophageal and transthoracic echo studies were performed in 129 patients with MS in chronic AF. Previous embolic events were documented in 45 patients, 20 of them within 6 months, and 65 patients were receiving long-term anticoagulation. The intensity of LASEC and mitral regurgitation, the presence of thrombi and active LA appendage flow (peak velocities > or = 20 cm/s), and LA volume as well as other conventional echo-Doppler determinations were investigated in every patient. The prevalences of significant LASEC (degrees 3+ and 4+), thrombus, active LA appendage flow, and significant mitral regurgitation (>2+) were: 52% (67 patients), 29.5% (38 patients), 32% (41 patients), and 36% (47 patients), respectively. Multivariate analysis showed that decreasing mitral regurgitation severity, absence of active LA appendage flow, and mitral valve area were the independent correlates of LASEC (odds ratio [OR] 3.7, 5.4, and 0.17, respectively; all p <0.02). Active LA appendage flow and anticoagulant therapy were associated negatively, whereas the severity of LASEC was associated positively with the finding of LA thrombus (OR 9.6, 3.9, and 1.6, respectively; all p <0.05). The intensity of LASEC and previous anticoagulant therapy (OR 1.74 and 4.5, respectively; p <0.005) were the independent covariates of thrombi and/or recent embolic events. In conclusion, the severity of mitral regurgitation and lack of active LA appendage flow were, respectively, the strongest independent correlates of significant LASEC and thrombus in patients with MS in chronic AF. LASEC remains the cardiac factor most strongly associated with thrombus and/or recent embolic events in these patients.

Role of transesophageal echocardiography in the assessment of patients with blunt chest trauma: Correlation of echocardiographic findings with the electrocardiogram and creatine kinase monoclonal antibody measurements

OBJECTIVES This study was designed to evaluate the usefulness of transesophogeal echocardiography (TEE) for detecting cardiac damage after blunt chest trauma (BCT). BACKGROUND Multiple methods have been used to detect cardiac damage after a BCT, but none has been demonstrated to be sensitive, specific, and feasible enough. METHODS This multicenter prospective trial was designed to evaluate the usefulness of TEE in the assessment of patients with BCT and to compare the TEE findings with those provided by the electrocardiogram (ECG) and cardiac isoenzymes assay. One hundred seventeen consecutive patients with a significant BCT were enrolled. A TEE was performed in each patient. Serial ECGs and plasma profiles of creatine kinase (CK) and CK-monoclonal antibody (MB) were obtained. RESULTS Sixty-six (56%) patients had pathologic findings in the TEE attributed to the BCT (group A). In the remaining 51 (44%) patients the TEE was normal (group B). An abnormal ECG was more frequent in group A (59% vs 24%; p < 0.001), and the serum CK-MB peak level was also higher in group A (174 +/- 30 U/L vs 93 +/- 21 U/L; p = 0.05). Relative to pathologic TEE findings, the sensitivity and specificity of an abnormal ECG were 59% and 73% and of high CK-MB with CK-MB/CK > 5% were 64% and 52%, respectively. CONCLUSIONS We conclude that TEE can be routinely and safely performed for diagnosing cardiac injuries after a BCT and plays an important role in the evaluation and treatment of these patients. EGG and CK-MB assay are not good methods for detecting cardiac damage in this setting.