Luis Sánchez-Harguindey

Natural history and serial morphology of aortic intramural hematoma: A novel variant of aortic dissection

BACKGROUND Acute aortic dissection is a cardiovascular emergency that requires prompt diagnosis and treatment. Transesophageal echocardiography is the current standard diagnostic imaging modality in many medical centers. Aortic intramural hematoma is a variant of aortic dissection whose natural history and prognosis have not been well studied. We performed transesophageal echocardiography in patients with aortic intramural hematoma to determine the echocardiographic characteristics and echocardiographic evolution of this lesion, impact on patient management, and patient outcome. METHODS AND RESULTS Twenty-one consecutive patients with aortic intramural hematoma confirmed anatomically (four patients) or with an additional diagnostic imaging technique (17 patients) underwent a transesophageal echocardiographic examination. Fifteen patients with longstanding hypertension had chest or back pain, and the intramural hematoma was visualized in the ascending aorta (n = 4), along the whole aorta (n = 4), in the descending aorta (n = 6), or in the aortic arch (n = 1). The thickening of the aortic wall was crescentic. Patients with ascending aortic intramural hematoma had the following results: two patients died suddenly, three patients underwent surgery because of increased aortic wall thickening (one patient) or secondary intimal tear (two patients), and the remaining three patients had regression of the hematoma. Patients with hematoma confined to the descending aorta and the patient with aortic arch involvement (n = 7) had a different result: one patient died from aortic rupture and the remaining six patients did well. Six patients had a traumatic aortic injury, and the intramural hematoma was located along the descending thoracic aorta. The thickening of the aortic wall was circular in five patients and crescentic in one. Three of these patients had normalized thickness of the aortic wall on follow-up transesophageal echocardiographic studies. The other three patients died from multiorgan system failure. Aortography showed a reduction of the diameter of the aortic lumen in four patients; diameter in the remaining 17 patients was normal. CONCLUSIONS Aortic intramural hematoma can be detected and monitored by transesophageal echocardiography but not by aortography. Two types of aortic intramural hematoma can be distinguished: (1) traumatic of good prognosis and (2) nontraumatic, which can be an early stage of the classic aortic dissection, with bad prognosis in cases involving the ascending aorta.

Reason for Discrepancies in Identifying Myocardial Viability by Thallium-201 Redistribution, Magnetic Resonance Imaging, and Dobutamine Echocardiography

Dobutamine echocardiography (DE), magnetic resonance imaging (MRI), and thallium redistribution (TS) are used to assess cardiac viability. However, these modalities sometimes yield contradictory results. Our aim was to establish the degrees of agreement among DE, MRI, and TS in identifying myocardial viability and to analyze the minimum critical mass of live (viable) cells required for each test to identify viability. A prospective study was done in which DE, MRI, and TS were consecutively performed in 10 ischemic patients scheduled for heart transplantation. The explanted heart was analyzed to quantify the amount of live cells per segment. The pathologic data were compared with the test results to analyze the minimum mass of viable cells required by each technique to identify viability. Mean age was 58 +/- 8 years (8 men). The mean ejection fraction was 0.27 +/- 0.04. Seven patients had severe cardiac failure (New York Heart Association functional class IV) and 6 patients had refractory angina. A total of 150 cardiac segments were analyzed. Among the 150 segments, 107 (71.3%) showed some degree of myocardial necrosis. Mean total area, mean fatty area, and mean necrotic area per segment were 2.53 +/- 0.7, 0.13 +/- 0.2, and 0.55+/-0.5 cm(2), respectively. As expected, a higher amount of necrotic tissue was found in nonviable segments. From the 150 segments, DE identified 90 as viable and 60 as nonviable. These data were similar to that of MRI (98 viable and 52 nonviable). A higher proportion of viable segments was found by TS (117 viable vs 33 nonviable). The concordance between DE and TS was only moderate (kappa 0.49). The agreement between MRI and TS also showed moderate concordance (kappa 0.56). The highest agreement was found between DE and MRI (kappa 0.73). Thus, discrepancies in assessing viability by DE, MRI, and TS may be due to differences in the minimum critical mass of live myocytes required by each technique to diagnose viability. Thallium requires a lesser amount of live tissue than DE or MRI to detect viability; also, its maximum diagnostic efficiency is obtained with lesser amounts of live tissue on each segment. These considerations should be taken into account when these diagnostic tests are used for the detection of viability before revascularization procedures.

Right Ventricular Asynergy During Dobutamine-Atropine Echocardiography

OBJECTIVES We sought to analyze right ventricular contractility during dobutamine infusion in patients with right coronary artery disease and to elucidate whether the development of right ventricular asynergy aids in characterizing a right coronary artery stenosis. BACKGROUND Clinical investigations are emphasizing the importance of right ventricular function in patients with coronary artery disease. Thus, prognosis of patients with inferior myocardial infarction is influenced by right ventricular function. This study describes the echocardiographic and electrocardiographic findings during dobutamine-atropine echocardiography in patients with right coronary artery disease. METHODS We studied 31 patients with isolated right coronary artery disease and no previous myocardial infarction. Six patients with poor acoustic window were excluded (feasibility 80%). The remaining 25 patients underwent dobutamine-atropine echocardiography. A right coronary artery stenosis located before the origin of the right ventricular branches was considered proximal; otherwise, it was considered distal. RESULTS Right ventricular asynergy during dobutamine-atropine testing developed in 17 patients (sensitivity 68%); 14 had proximal and 3 had distal right coronary artery disease. The following segments were involved: inferior (n = 17), lateral (n = 5) and outflow tract (n = 1). No patient showed anterior asynergy. All 17 patients had left ventricular asynergy as well. Ischemia-free time was 10.7 +/- 6.2 (mean +/- SD) min for the right ventricle and 8.9 +/- 5.2 min for the left ventricle (p < 0.05). Ischemic ST changes were recorded in 15 patients (in standard leads in 14 and in right precordial leads in 8). All patients with right precordial changes showed ST elevation and had right ventricular asynergy (sensitivity and specificity for right ventricular asynergy 47% and 100%, respectively). A control group of 25 patients with no right coronary artery disease (5 with no disease, 15 with left anterior descending and 5 with left circumflex coronary artery disease) underwent dobutamine echocardiography. Right ventricular asynergy developed in two patients with left anterior descending artery stenosis (specificity 92%); in both, the anterior wall was affected. CONCLUSIONS Echocardiography during dobutamine infusion is a reliable technique for assessing right ventricular dysfunction in patients with right coronary artery disease. Right ventricular contractility can be assessed during dobutamine echocardiography in selected patients.

Chlamydia pneumoniae in the atherosclerotic plaques of patients with unstable angina undergoing coronary artery bypass grafting: does it have prognostic implications?

OBJECTIVE This study sought to evaluate the prognostic significance of the presence of DNA of Chlamydia pneumoniae in the coronary atherosclerotic lesions of patients with unstable angina. BACKGROUND C. pneumoniae has been implicated in the pathogenesis of coronary artery disease by serological and pathological studies, but whether antichlamydial antibodies and the presence of this pathogen in the coronary atherosclerotic tissue are related to prognosis in unstable angina remains unclear. METHODS A total 76 coronary specimens from 45 patients with unstable angina undergoing bypass surgery were subjected to nested polymerase chain reaction (PCR) for C. pneumoniae. Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) were also examined by an enzyme immunoassay. Patients were followed during a 2-year period to determine the incidence of adverse cardiovascular events. RESULTS DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions: 39 patients showed a positive PCR result in at least one plaque. Of the 45 patients, 44 (97.7%) showed a positive serological result: IgG was positive in 39 (86.6%) patients, IgM in five (11.1%) patients and IgA in 42 (93.3%). Clinical characteristics and serologic results were similarly distributed in patients with and without infected lesions at enrollment. At least one adverse event occurred in 21 (46.6%) of the 45 patients at 2 years: death in nine (20%), recurrent angina in 12 (26.6%), revascularization in six (13.3%) and myocardial infarction in two (4.4%) patients. The composite endpoint of death, myocardial infarction, recurrent angina and revascularization at 2-year follow-up did not differ according to the PCR or serologic results. CONCLUSIONS The presence of C. pneumoniae in coronary atherosclerotic plaques of patients with unstable angina undergoing coronary bypass grafting does not have prognostic significance. In addition, serology does not allow us to differentiate those patients with plaque infection by C. pneumoniae and also does not provide any prognostic information in these patients.

Primary Mycotic Aneurysm of the Ascending Aorta Diagnosed by Transesophageal Echocardiography

Primary mycotic aneurysms are rare, and they can be difficult to diagnose before rupture. Early diagnosis is the cornerstone to effective management. Preoperative diagnosis has traditionally involved angiography and computed tomography. We report a case of Staphylococcus aureus aortitis with an aortic wall abscess and posterior pseudoaneurysm formation involving the ascending aorta in which transesophageal echocardiography was fundamental in diagnosis and patient management.

Contrast agents provide a faster learning curve in dipyridamole stress echocardiography

Aim: Interobserver variability is an important limitation of the stress echocardiography and depends on the echocardiographer training. Our aim was to evaluate if the use of contrast agents during dipyridamole stress echocardiography would improve the agreement between an experienced and a non-experienced observer in stress echo and therefore if contrast would affect the learning period of dypyridamole stress echo. Methods and results: Two independent observers without knowledge of any patient data interpreted all stress studies. One observer was an experienced one and the other had experience in echocardiography but not in stress echo. Two observers analysed 87 non-selected and consecutive studies. Out of the 87 studies, 46 were performed without contrast administration, whereas i.v. contrast (2.5 g Levovist® by two bolus at rest and at peak stress) was administered in 41. In all cases, second harmonic imaging and stress digitalisation pack was used. The agreement between observers showed a κ index of 0.58 and 0.83 without and with contrast administration, respectively. Conclusions: The use of contrast agents provides a better agreement in the evaluation of stress echo between an experienced and a non-experienced observer in stress echo. Adding routinely contrast agents could probably reduce the number of exams required for the necessary learning curve in stress echocardiography.

Disección intramiocárdica postinfarto de la pared posterior del ventrículo izquierdo con comunicación con el seno coronario

Paciente diabetica de 83 anos ingresada en nuestro centro por infarto agudo de miocardio posteroinferior en evolucion. Al cuarto dia de estancia presento un soplo pansistolico en mesocardio y apex de nueva aparicion. El ecocardiograma transtoracico puso de manifiesto acinesia de la pared posterior e inferior con imagen indicativa de diseccion de la pared posterior del ventriculo izquierdo, que se originaba en el segmento medio-distal de la misma, con orificio de entrada de 7 mm de diametro. Se apreciaba flujo turbulento en el interior de la auricula derecha, indicativo de proceder del seno coronario. Con el ecocardiograma transesofagico se confirmo la diseccion intramiocardica de la pared posterior del ventriculo izquierdo y su comunicacion con el seno coronario, identificando el flujo turbulento de la auricula derecha como procedente del mismo. Tras optar por el tratamiento medico, la paciente ha sido seguida por espacio de dos anos. El diametro del orificio de entrada del trayecto disecante permanecio sin cambios, si bien se observo crecimiento del diametro de la zona disecada y del seno coronario, aunque no dilatacion significativa de las cavidades derechas.

Ecocardiografía de estrés en el preoperatorio de cirugía vascular: ¿son comparables los resultados con dipiridamol y dobutamina?

Introduction. Perioperative cardiovascular complications are an important cause of post-surgical morbility and mortality in patients undergoing major vascular surgery. Dobutamine Stress Echo is considered one of the methods of choice in the detection of coronary artery disease in this subgroup of patients. Objectives. Our aim was to analyze if dipyridamole stress echocardiography could be used as an alternative to Dobutamine Stress Echo in the perioperative evaluation of patients in need of major vascular surgery. Patients and method. The result of consecutives dypiridamole and dobutamine stress exams prior to vascular surgery were reviewed. We analyzed if those patients with a positive stress echo presented a higher number of cardiac events during and after surgery than those with negative stress echo. The negative and positive predictive values were calculated for both techniques. Results. 133 stress exams were analysed: 39 with dobutamine and 94 with dipyridamole. Of the 39 dobutamine studies 2 were positive, 29 negatives and 8 non conclusive. Of the 94 dypiridamole studies 13 were positive and 81 negatives. None of the patients with a positive dobutamine echo underwent surgery. The negative predictive value for dobutamine echo was 96.5%, quite similar to that of dypiridamole stress echo (97.5%). Conclusion. Dipyridamole stress echocardiography is a valid alternative to dobutamine echocardiography in the pre-surgical evaluation of patients undergoing major vascular surgery.

Aneurismas coronarios múltiples en un varón joven. Aproximación diagnóstica mediante diferentes técnicas

Los aneurismas coronarios en el adulto son una entidad infrecuente. Su origen puede ser arteriosclerotico, congenito o deberse a otras causas menos habituales. Su manifestacion inicial puede ser el infarto de miocardio y la muerte subita, como consecuencia de su rotura o por la existencia de trombos intracoronarios. El metodo diagnostico de eleccion es la coronariografia, sin embargo, las tecnicas no invasivas como la ecocardiografia transtoracica y la resonancia magnetica nuclear pueden tener un papel de relevancia a la hora de detectar y seguir estas anomalias. Presentamos el caso de un varon joven con aneurismas coronarios multiples arterioscleroticos, que fueron valorados mediante pruebas no invasivas.

Isovolumic Contraction Time by Pulsed-Wave Doppler Tissue Imaging in Aortic Stenosis

BACKGROUND Doppler Tissue Imaging (DTI) has been evaluated in ischaemic heart disease and some cardiomyopathies. In patients with aortic stenosis (AS), left ventricular contraction is slowered. This study aimed to evaluate the possible role of the measurement of isovolumic contraction time (ICT) by DTI in the evaluation of AS severity. METHODS The study population constitutes 30 patients: 15 with AS (nine severe and six non-severe) and 15 control subjects. All of them had normal systolic function, sinus rhythm, and absence of ischaemic heart disease of conduction abnormalities. ICT was defined as the time from the onset of the QRS complex to the beginning of the DTI systolic wave. The correlation between ICT and aortic area obtained by continuity equation, as well as the diagnostic value of ICT in the identification of severe AS were studied. RESULTS ICT was significantly increased in patients with severe AS (98+/-27 versus 65+/-21 ms, p=0.024). There was a significant correlation between ICT and aortic area (r=-0.56; p=0.035). The receiver operator characteristic curve of ICT in the identification of severe AS yielded an area under the curve of 0.852 (95% confidence interval: 0.665-1.0). The two best cut-points were >73 ms (88% sensitivity, 77% specificity) and >85 ms (78% sensitivity, 83% specificity). A value of >41 ms had a 100% sensitivity, but only a 17% specificity, and >91 ms showed a 100% specificity, but only a 44% sensitivity. CONCLUSIONS ICT measured by pulsed-wave DTI is increased in patients with aortic stenosis.