Clinical value of myocardial performance index in patients with isolated diastolic dysfunction

AIMS

The Doppler-derived myocardial performance index (MPI) has been considered as a diagnostic and prognostic Doppler marker for many different clinical conditions. The purpose of this study was to determine the diagnostic accuracy of traditional Pulsed-wave Doppler (PWD-MPI) and Pulsed-wave tissue Doppler imaging (TDI-MPI) and the degree of agreement between these methods in patients with grade-I diastolic dysfunction (DDI) and a normal ejection fraction.

METHODS

Forty-seven consecutive ambulatory patients with DDI were compared to 51 healthy subjects with normal echocardiograms. All subjects underwent measurement of time intervals and MPI with PWD and pulsed TDI.

RESULTS

TDI-MPI and PWD-MPI were significantly higher in patients with DDI than in control subjects: 0.49 ± 0.14 vs. 0.40 ± 0.09 (P < 0.001) and 0.45 ± 0.11 vs. 0.37 ± 0.08 (P < 0.001), respectively. Cutoff values of TDI-MPI > 0.42 and PWD-MPI > 0.40 identified DDI subjects, with sensitivities of 74 and 64%; specificities of 61 and 69%; positive likelihood ratios of 1.9 and 2.0; and negative likelihood ratios of 0.42 and 0.53, respectively; no significant difference was noted between the areas under the ROC curves of TDI-MPI and PWD-MPI (P = 0.77). Bland-Altman plots showed wide limits of agreement between these indices: - 0.17 to 0.23 in healthy subjects and - 0.24 to 0.32 in DDI patients.

CONCLUSION

PWD-MPI and TDI-MPI showed poor clinical agreement and were not reliable parameters for the assessment of left ventricular diastolic function.

Teaching basic life support to students of public and private high schools

BACKGROUND

Despite being recommended as a compulsory part of the school curriculum, the teaching of basic life support (BLS) has yet to be implemented in high schools in most countries.

OBJECTIVES

To compare prior knowledge and degree of immediate and delayed learning between students of one public and one private high school after these students received BLS training.

METHODS

Thirty students from each school initially answered a questionnaire on cardiopulmonary resuscitation (CPR) and use of the automated external defibrillator (AED). They then received theoretical-practical BLS training, after which they were given two theory assessments: one immediately after the course and the other six months later.

RESULTS

The overall success rates in the prior, immediate, and delayed assessments were significantly different between groups, with better performance shown overall by private school students than by public school students: 42% ± 14% vs. 30.2% ± 12.2%, p = 0.001; 86% ± 7.8% vs. 62.4% ± 19.6%, p < 0.001; and 65% ± 12.4% vs. 45.6% ± 16%, p < 0.001, respectively. The total odds ratio of the questions showed that the private school students performed the best on all three assessments, respectively: 1.66 (CI95% 1.26-2.18), p < 0.001; 3.56 (CI95% 2.57-4.93), p < 0.001; and 2.21 (CI95% 1.69-2.89), p < 0.001.

CONCLUSIONS

Before training, most students had insufficient knowledge about CPR and AED; after BLS training a significant immediate and delayed improvement in learning was observed in students, especially in private school students.

Congenital heart diseases in the newborn: from the pediatrician's request to the cardiologist's evaluation

OBJECTIVE

To analyze the importance of symptoms as a reason for referral to pediatric cardiologists in the diagnosis of congenital heart diseases (CHD) in the newborn (NB).

METHODS

Prospective study on live NB referred for cardiac evaluation, with performance of electrocardiogram, chest radiography and echocardiography. Cardiology consultation was requested by means of a multiple-choice form including signs and symptoms suggestive of CHD. Patent ductus arteriosus (PDA) without clinical and/or hemodynamic consequences was not considered a heart disease.

RESULTS

From 1999 to 2002, 358 out of 3716 NB were studied, and 49 cases of CHD and 128 of PDA were found. The prevalence of CHD was 13.2:1000 NB. The main reason for referral to the cardiologist was heart murmur in 256 (72%) NB, of which 39 (15%) had CHD, and in 91% of the 128 cases of PDA. In 14 (4%) NB, the reason for referral was cyanosis, and eight of these patients (57%) had a CHD. Heart failure was the reason for referral in 37 (10%) NB, of whom 17 (46%) had CHD. Arrhythmia, associated congenital malformations, or chromosome disorders were the reasons for referral in 14% of the cases.

CONCLUSION

The main reason for referral was detection of a heart murmur on cardiac auscultation. Although cyanosis and heart failure were uncommon reasons for referral, their presence indicated a high probability of the diagnosis of heart disease. Pediatric screening plays a key role in this diagnosis.