Archivos del Instituto de Cardiologia de Mexico最新文献

Blood pulse wave velocity (PWV) is a known index of arterial rigidity and its measurement has proved its usefulness in the study of some cardiovascular pathologies. In this study we describe the design and implementation of a system for noninvasive PWV determination in the aorto-braqui-humero-radial (A-->h), aorto-ileo-femoro-pedial (A-->f) and aorto-carotid (A-->c) regions. This system was examined with 36 normotensives (NT) and 34 hypertensives (HT) patients with (LVH, n = 20) and without (WLVH, n = 14) left ventricular hypertrofy. The equipment consist of a personal computer with an analog to digital converter and hardware and software items adapted to take simultaneously the electrocardiogram (ECG), two photopletismographic pulses and one oscilometric pulse. The Q-pP interval (time between a Q ECG wave and distal blood pulse) and the distance to the register sites are taken into account to calculate the beginning of cardiac prexpulsive period (time zero of pulse trip) which allow the determination of the PWV (in meters/second) from the aortic root to the distal point of the via. PWV was significant higher (p < 0.001) in HT vs. NT (A-->h: 9.3 +/- 2.6 vs. 7.2 +/- 0.8, A-->c: 9.5 +/- 2.8 vs. 6.0 +/- 1.9 and A-->f: 9.5 +/- 1.8 vs. 7.2 +/- 0.9) in each evaluated arterial region. Same thing occurred in cases with LVH vs. WLVH (A-->h: 10.5 +/- 1.6 vs. 8.0 +/- 1.9, A-->c: 10.2 +/- 1.9 vs. 8.0 +/- 1.9 and A-->f: 10.5 +/- 2.0 vs. 8.6 +/- 1.2) (p < 0.025). This is consistent with the relationship more pressure [symbol: see text] more rigidity and with other reports. This method may have clinical application.

Chagas disease was described in Mexico by Mazzotti in 1940. Post-transfusional cases have not been described. We report proved case of acute chagasic cardiopathy in a nine months old infant with suspected transfusional infection during neonatal period. She was treated with nifurtimox with disappearance of parasites and regression of cardiopathy. She is asymptomatic nine years afterwards with normal growth and negative parasitology and serology.

This study shows that the hydantoin drug, dantrolene, protects against myocardial damage induced by reperfusion. This effect was analyzed after 5 minutes of left coronary artery occlusion in Wistar rats hearts. The results made evident that dantrolene protects the myocardium against myocardial dysfunction (stunning heart) and reperfusion arrhythmias. Furthermore, it decreases the release of the enzymes creatine cinase and lactate dehydrogenase to the plasma, and protects from the structural damage of myocardium. We propose that the protective effect of the drug, might be due to its blocking effect on cardiac calcium release channel (ryanodine receptor) of the sarcoplasmic reticulum; thus, decreasing the high level of cytoplasmic calcium concentration (calcium overload), that is a characteristic of reperfusion injury.

Between december of 1994 and june 1997, 90 children and adolescents were referred to the Shaio Clinic Foundation for evaluation of recurrent unexplained syncope. Head-up tilt testing was positive in 45 (50%), 23 male, with a mean age of 12.7 years (range 5-17 years). The response during Head-up tilt testing was predominantly vasodepressor (57%), followed by mixed in 24% and cardioinhibitory in the remaining 17%. The majority of patients had a positive response during pharmacological phase with isoproterenol infusion at a mean time of 17 +/- 8 minutes. Head-up tilt is a safe diagnostic test and defines the cause of unexplained syncope in up to 50% of children and young adults with recurrent syncope. The management was based on education, control of risk factors and psychological and/or physical rehabilitation. In the 15.2 months follow up we observed complete remission or a significant reduction of symptoms in 95% of the cases. Only 5% of the patients persisted or had worsening of their symptoms.

Purpose: To assess the results of reocclusion procedures for late residual shunts after transcatheter closure of the patent ductus arteriosus.

Material and methods: Nineteen patients underwent reocclusion procedures either with Rashkind technique (2 patients) or with coils. Mean age was 96.5 months and mean interval between the initial and the additional procedure was 15.7 months. In 5 patients, the duct was balloon-dilated prior to occlusion.

Results: In 3 patients the procedure was unsuccessful because it was impossible to cross the duct using either a guide wire or a catheter. Immediate or late complete occlusion occurred in 13 patients. Two patients required a third procedure for complete closure. One patient developed severe intravascular hemolysis after coil implantation and was sent to surgery. The rate of final late residual shunting decreased from 17.1% to 6.6% (5/76) in the umbrella group and from 15.8% to 1.8% (1/56) in the coil group.

Conclusions: Reocclusion procedures are indicated after one year of persistent shunting following the primary procedure. They are generally effective and reduce significantly the rate of late residual shunting. In patients with tiny shunts, the duct may need to be dilated. Coils are preferred because of their low cost.

The purpose of this study was to evaluate the immediate and long term results of pulmonary valve ballon dilation, and to determine the prognostic factors of failure in 109 patients (60 female and 49 male), aged 7.04 +/- 8.4 years. Seventy two patients (66.1%) had isolated valvular stenosis and 33.9% presented associated lesions. Peak systolic pressure gradient across the pulmonary valve decreased from 89.53 +/- 37.23 to 20.8 +/- 19.41 mmHg (p < 0.0001) after valvuloplasty. Forty three patients developed reactive infundibular stenosis after valvuloplasty with a systolic gradient of 19.65 +/- 35.64 mmHg. At a mean period of 8 years of follow-up the pressure gradient was 20.75 +/- 14.32 (p < 0.001). Valvuloplasty was successful in 86.2% of the cases with a global mortality of 1.9%, minor complications in 15.2%, and a failure rate of 13.8%. At follow-up restenosis developed in 6.7%. The comparative analysis between the groups of success and failure yield as significant risk factors for failure an age younger than 3.5 years and a pulmonary valve with displastic (p < 0.05) or combined morphology (p < 0.05). This group had also more complications and higher systolic gradients and right ventricular pressures post-dilation (p < 0.05). Pulmonary valvuloplasty is a safe and effective procedure for the treatment of pulmonary valve stenosis with a good immediate and long-term results, and is now considered the treatment of choice.