[Factors that affect DNA content analysis by flow cytometry]. / Aspectos que afectan el análisis de contenido de ADN por citometría de flujo.

DNA ploidy and cell cycle analysis by flow cytometry is used to obtain additional information about the diagnosis and prognosis of different types of cancer. However, there are several disagreements among authors about the tissue source (fresh-frozen or paraffin embedded), cellular dissociation methods (mechanical, enzymatic or other), use of different dyes, lasers, analysis software with different mathematical models and interpretation of results. A discussion about the different aspects that affect the study of DNA ploidy and cell cycle and a consensus in publications is mandatory. A strict control of analysis processes and data interpretation is also necessary.

[Percutaneous mitral valvuloplasty: immediate and late results in 300 patients]. / Valvuloplastía mitral percutánea: resultados inmediatos y tardíos en 300 pacientes.

Between December 1987 and July 1992, we performed a balloon mitral valvuloplasty to 300 patients aged 48 +/- 23 years, with pure or predominant, symptomatic mitral stenosis, with an hemodynamic area < 1.5 cm2 and a mean echocardiographic score of 8.8 +/- 1.3 (6-13). Young subjects with mobile and flexible valves as well as elders with highly damaged valves were included. A transeptal technique employing 2 balloons was used in 97% of cases. There were 3 failures and 9 deficient results. In 284 patients, the procedure was considered successful with a mean increase in mitral area (measured using modified Gorlin's formula) from 0.88 +/- 0.13 to 2.19 +/- 0.38 cm2. Four patients died two due to a left ventricular traumatism, one due to an irreversible low cardiac output and one due to a massive systemic embolism. In five, a cardiac tamponade was treated with pericardiocentesis or surgery. One hundred patients were followed for a mean of 40 +/- 3 months. Mitral areas remained over 1.5 cm2 in 87% and 14 had a significant reestenosis. The latter had an initial echocardiographic score over 8 or previous surgical commissurotomy. Multifactorial analysis identified valvular motility and global echocardiographic scores as predictors of immediate success. Likewise, the last parameter and subvalvular thickening were predictors of late reestenosis and of increase in mitral regurgitation post valvuloplasty. According to our experience, percutaneous balloon mitral valvuloplasty is a first choice therapeutic alternative in patients with mitral stenosis.

[Percutaneous aortic valvuloplasty in the adult: immediate results and follow-up of 43 patients]. / Valvuloplastía aórtica percutánea en el adulto: resultados inmediatos y seguimiento en 43 pacientes.

From June 1986 to June 1991, percutaneous balloon valvuloplasty was performed in 43 patients with severe symptomatic aortic stenosis. Their age ranged from 52 to 81 years (mean 69). The retrograde approach was used in 34 and the transseptal technique in the remaining 9. One patient died from severe tamponade, another developed a large cerebral infarct and the procedure failed in a third. The procedure was considered successful in the remaining 36 patients. Cardiac output increased from 3.5 +/- 0.6 to 4.7 +/- 0.7 l/min, (p < 0.01) and aortic valve area from 0.53 +/- 0.21 to 0.97 +/- 0.2 cm2 (p < 0.01). After a follow up period of 24 +/- 9 months 3 patients, all with initially poor results, died. 10 of 19 patients with adequate initial results experimented a deterioration of functional class. The other 9 patients have preserved the initial improvement obtained with dilatation. Thus percutaneous aortic valve dilatation in adults with severe aortic stenosis is risky and of limited clinical value.

[Antihypertensive effect of isradipine: blood pressure determination with continuous ambulatory monitoring]. / Efecto antihipertensivo de isradipino: evaluación con monitorización ambulatoria continua de la presión arterial.

A 24 hr blood pressure monitoring system (Medilog ABP) was used to evaluate the efficacy of isradipine, 2.5 mg q 12 hr for 2 weeks, in 26 hypertensive patients. During a pretreatment control period of 4 weeks a diastolic pressure above 95 mmHg on non pharmacologic measures was verified in each patient. A significant decrease in systolic and diastolic blood pressures compared at 2 hr intervals was observed after treatment with isradipine. Treatment was not associated to modification of the circadian rythm in blood pressures.

[Percutaneous mitral valvuloplasty as a treatment of choice for mitral stenosis. Immediate results and long-term follow-up]. / Valvuloplastía mitral percutánea como tratamiento de elección de la estenosis mitral. Resultados inmediatos y seguimiento alejado.

We evaluated 77 patients with symptomatic mitral stenosis for balloon valvuloplasty. Five patients were excluded from the procedure due to the presence of intra-atrial thrombi or mitral valve endocarditis as detected by 2D echocardiography. The mean age of the 72 treated patients was 38 +/- 11 years, 68 were NYHA functional class II or IV: only 6 patients had valvular calcification. Three patients had severe liver failure, 2 were chronic alcoholics, one had liver cirrhosis, 2 had severe weight loss and 13 had pulmonary hypertension at systemic levels. 69 patients had a technically adequate procedure, one patient died, 1 developed cardiac tamponade and 1 failed. Mitral valve area increased from 0.93 +/- 0.34 to 2.38 +/- 0.67 cm2. Mitral incompetence increased in only 16 patients. After a mean follow up period of 15 +/- 5 months (range 8 to 27), 56 patients remained in FC I or II. Mitral valve area remained satisfactory in 54 patients. Mitral valve anatomy evaluated by echocardiography is helpful to predict immediate and late outcome. We conclude that balloon mitral valvuloplasty is the first choice for patients with severe symptomatic mitral stenosis.

[Left ventricular relaxation in myocardial diseases. Hemodynamic study]. / La relaxation ventriculaire gauche dans les maladies myocardiques. Etude hémodynamique.

Left ventricular relaxation as opposed to contraction, was studied by recordings of left ventricular pressure and its first derivation in primary hypertrophic cardiomyopathy without obstruction (25 cases, Group II) in primary dilated cardiomyopathy (33 cases, Group III) and in normal subjects (22 cases, Group I). Simultaneous recording of the pressure, the first derivation and intraventricular and intraaortic phonocardiogrammes showed the significance of certain features of the tracings and allowed a simplified protocol: ventricular relaxation was then defined from the pressure tracing (high fidelity recording) and its first derivation. The onset of isovolumic relaxation corresponded to the point of inflection on the descending part of the first derivation tracing, preceding its negative peak by an average of 0.02 s. The end of isovolumic relaxation corresponded to the crossing point of the atrial and ventricular pressure curves. In the absence of atrial pressure tracings the initial part of the rapid filling phase was included as far as the return of the first derivation tracing to its baseline (early diastole on the ventricular pressure tracing) as the duration of this period seemed remarkably constant (0.07 s). The parameters studied were: duration of isovolumic relaxation or the period defined above including the rapid filling phase; the average rate of fall of left ventricular pressure during this part of diastole; the value of the negative peak of the first derivation (dp/dt min); the rate of lengthening of the contractile elements at minimum dp/dt (dp/dt min/28P). Changes in relaxation were obvious in the pathological groups. The duration was increased and its average speed, dp/dt min, and dp/dt min/28 P were reduced. In the hypertrophic group, however, these changes seemed to be primary and contractility was usually unaffected. In dilated cardiomyopathy these changes could be considered secondary to decreased contractility. The hypothesis that changes in relaxation are specific for hypertrophic forms, and that changes in contractility are specific for dilated forms of primary cardiomyopathy may therefore be proposed.