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E Alexánderson

Publications and source records attributed to E Alexánderson.

13 recordsLinked to original sources
PubMedDate not supplied

[The thickness/radius ratio (h/r) of the left ventricle in pure mitral insufficiency].

We studied 11 patients with severe mitral regurgitation (MR). With 2-D echocardiogram we could obtain the septal and posterior wall thickness, left ventricular internal dimensions and ventricular function. With parasternal short axis view we calculate the h/r ratio (left ventricular thickness/radius). The results were compared with normal values: we found important left atrial and ventricle dilatation with significative difference from the normal values (P < 0.001), the diastolic and systolic h/r ratio was significative lower than the normal values (P < 0.005): the systolic wall stress was significative higher in relation to normal values (P < 0.001). We conclude that patients with severe (MR) initially have an important ventricular dilatation but no hypertrophy despite volume overload. The possible explanation is that in early stages of the disease, the afterload of the left ventricle is low and does not trigger the development of hypertrophy. The hypertrophy appears only when the systolic stress is high secondary to myocardial failure. The excessive dilatation of the left ventricle probably damages the myocardial fibers by excessive stretch. This mechanism probably explains the poor late surgical evolution of patients with mitral prosthesis. This we propose that the optimal surgical timing for such patients is when the systolic wall stress elevates over the normal limits, because this is an early sign of myocardial failure.

Adolescent↗
PubMedDate not supplied

[Rupture of the interventricular septum in acute myocardial infarct].

Ventricular septal rupture in patients with acute myocardial infarction is not a common complication. It was found in 20 patients of 4298 admitted to the coronary care unit of the Instituto Nacional de Cardiología Ignacio Chávez from January 1980 to March 1991. The diagnosis was made by right heart catheterization if 85%, by echocardiography in 35% and by postmortem study in 15% of the patients. Mortality was 70%. In all patients the functional class worsened after the rupture, from class I to III or IV. There were not significant differences in mortality in relation to risk factors, or hemodynamic findings. Mortality was higher in older patients, females and patients with anterior myocardial infarction. Angiographic studies did not increase mortality and are necessary to establish an early surgical treatment.

Age Factors↗
PubMedDate not supplied

[The clinical and electrophysiological characteristics of patients with idiopathic ventricular tachycardia].

Clinical and electrophysiological characteristics in 20 patients with clinical ventricular tachycardia and normal hearts documented by physical examination, echocardiography, and angiocardiography were analysed. There were 11 males and 9 females. All patients had sustained ventricular tachycardia without hemodynamic instability during tachycardia. A right bundle branch block morphology of ventricular tachycardia was present in 14 patients and left bundle branch block morphology in six patients. During electrophysiologic studies, ventricular tachycardia was induced in 10/15 (66%) patients. Intravenous verapamil terminated the ventricular tachycardia in 9/10 (90%) of cases. However oral verapamil not prevented recurrences. Among 14 patients on whom exercise tests were performed, only two had exercise-induced ventricular/tachycardia. Late potentials were positive in 3/14 (21%) cases and one patient died suddenly during exercise without antiarrhythmic drugs.

Adolescent↗
PubMedDate not supplied

[An assessment of myocardial ischemia in women with the exercise test validated by coronary angiography].

Ischemic heart disease has been studied in men and women only as a group. We studied the sensitivity and specificity of the exercise stress testing in women. The exercise stress testing (EST) was validated with the coronary arteriography. We studied 72 women and 129 men, the mean age was 55 years for women and 51 years for men. We found in women 83.2% of estimated maximal heart rate; the rate pressure product was 2.4, no different from the values recorded in men (p greater than 0.06). The blood pressure response to exercise was higher in women, and the maximal work capacity was more elevated in men (p less than 0.006). We found normal coronary arteries in 41 women, 70.7% with a positive (EST) compared with a 87.07% in men. The sensitivity and specificity of the exercise stress testing for the diagnosis of ischemic heart disease is smaller in women.

Coronary Angiography↗
PubMedDate not supplied

[Myocardial viability].

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Angioplasty, Balloon↗
PubMedDate not supplied

[Acute myocardial infarction related to cocaine use. Report of a case].

Cocaine use has been associated with ischemic syndromes, especially angor pectoris, myocardial infarction, cardiac arrhythmias and sudden death. A significant number of persons suffering from myocardial infarction associated with cocaine abuse do not have significant coronary atherosclerosis, and the mechanism for infarction in these patients have remained obscure. This report describes a young man with angiographically normal coronary arteries in whom cocaine abuse probably produced coronary artery spasm leading to coronary thrombosis and infarction.

Adult↗
PubMedDate not supplied

[Simultaneous assessment of perfusion and myocardial viability with 2 isotope studies (thallium at rest and sestamibi in exercise). Initial experience in Mexico and Latin America].

UNLABELLED: Rest-stress sestamibi single photon emission computed tomography (SPECT) has sensitivity and specificity similar to those of thallium 201 SPECT for detection of coronary artery disease. However, sestamibi is not ideal agent to study myocardial viability. There is not published experience in Latin American using dual isotope SPECT protocol to evaluate myocardial perfusion and viability. We studied 44 consecutive patients with coronary artery disease, 37 of them with previous myocardial infarction. Coronary angiography was performed in all patients. We used a 3 mCi rest T 201 SPECT followed by stress and 25 mCi sestamibi injection. Sestamibi SPECT was performed 30 minutes after exercise or 1 hour after pharmacologic stress with dipyridamole. To validate perfusion findings patients returning next day for rest sestamibi injection and SPECT. Scintigraphic data were read by two blinded expert using 20 SPECT segment analysis and each segment was scored using 5 points scoring system (0 = normal, 4 = absent uptake). The segmental score agreement between rest thallium 201 and rest sestamibi and the comparison of defect reversibility percentage and non reversibility between both protocols was 90.7%. CONCLUSION: Separate acquisition dual isotope myocardial perfusion SPECT is accurate for coronary artery disease evaluation. It showed a good agreement with rest-stress sestamibi SPECT for assessment of rest perfusion defects and reversibility and it was a better method to evaluate myocardial viability.

Exercise Test↗
PubMedDate not supplied

[Usefulness of SPECT (single-photon emission-computed tomography) in the detection of coronary disease].

OBJECTIVE: To evaluate the clinical usefulness of cardiac SPECT in the detection of coronary artery disease, and the relation with the site, number and severity of the angiographic lesions. METHOD: We studied 216 patients; with myocardial perfusion imaging with SPECT (T1-201 and/or Tc-99 Sestamibi) and coronary angiogram. We defined the localization of myocardial perfusion defects (anterior, inferior, septal, lateral or apex), and their correlation with coronary angiogram, based on the location, number and severity of coronary angiographic lesions. We considered significative coronary stenosis obstructions of 60% or more. RESULTS: Of the 216 patients studied, 181 (83.8%) were male and 35 (16.2%) female. Age ranged between 30 and 82 years; 143 males and 23 females had a previous myocardial infarction. The SPECT sensitivity for diagnosing ischemia of one, two and three vessel disease was 94%, 96% and 100%. The sensitivity for diagnosing disease in specific vascular territories was 91.6% for LAD 100% for RCA, 92.8% for CX and 100% for left main. CONCLUSIONS: Myocardial perfusion imaging with SPECT has high sensitivity for diagnosing coronary artery disease. The sensitivity and specificity were more accurate in proximal anterior descending artery disease, left main and three-vessel coronary artery disease. We found correlation in the site, number and severity of the angiographic lesions and in myocardial perfusion defects.

Adult↗