Correlates of Tc-99m tetrofosmin pulmonary uptake in patients with coronary artery disease and subjected to high dose dipyridamole stress

The stress-lung-to-heart ratio [LHR] of uptake of the tracers during myocardial perfusion imaging [MPI] has been shown to have diagnostic significance for the severity of the disease and left ventricular [LV] dysfunction in patients with coronary artery disease [CAD]. On the other hand, high-dose dipyridamole [HDD] stress myocardial single photon emission computed tomography [SPECT] has greater accuracy for determination of CAD severity than standard dose dipyridamole [SDD] or exercise stress [EST]. To test whether the stress LHR of Tc-99m tetrofosmin [Tc-99m TF] uptake is a determinant of the severity of CAD and left ventricular dysfunction in patients with CAD and subjected to high-dose dipyridamole [HDD] stress. This retrospective study comprised 39 patients with angiographically-proved CAD [group I] and 8 subjects [group II] with negative MPI [gated rest and stress; one-day protocol] and normal coronaries that have been subjected to MPI using Tc-99m TF under HDD [0.84mg/kg over 4 min.]. The LHR of Tc-99m TF uptake was calculated by area of interest [AOI] analysis for the normalized myocardial and right lung counts from the immediate post-stress anterior chest view. The LV transient ischemic dilation [LVTID] was visually-interpreted; while the summed stress score [SSS] and rest LV function parameters were calculated. Further grouping of all subjects into 0-2 vessels CAD [group A] and main stem/3 vessel CAD [group B] was performed. The mean LHRs were 0.48 +/- 0.09 SD and 0.39 +/- 0.07 SD in groups I and II respectively [P>0.05]. The LHR of all subjects showed significant positive correlations with the SSS mid LV volumes and significant inverse correlation with LVEF [P<0.001 each] with no significant correlation with LVTID [P>0.05]. The LHRs were 0.44 +/- 0.08 SD and 0.57 +/- 0.08 SD in groups A and B respectively [P<0.001]. High dose dipyridamole [HDD] is a safe mode of stress to evaluate patients with CAD who are unable to exercise. The lung-to-heart ratio of Tc-99m tetrofosmin [immediately post HDD stress] seems to be a diagnostic marker to elicit the severity of CAD as well as the systolic and diastolic LV dysfunction in such patients

ECHO-Doppler evaluation of systolic murmurs in infancy

Echo- Doppler with colour flow mapping technique was carried out on 15 full term neonate infants and on 55 infants aging from 1-24 months who presented with systolic murmurs over a period of 18 months. This was done to evaluate the clinical value of ECG and echodoppler in assessment of systolic murmurs in infancy. Among the 15 neonates only 3 cases [20%] were found free echocardiographically and the other 12 [80%] had different pathologic echocardiographic findings. On the other hand, in the 55 studied infants [ages from 1-24 months], echocardiographic study revealed no cardiac abnormalities in 31 cases [56%], while definite heart disease was present in 24 cases [44%]. The initial referral diagnosis of the systolic murmur [innocent vs pathologic] was correlated with the echocardiographic finding. On clinical examination, 65% of the murmurs were initially evaluated as inoccent and the other 35% pathologic. The clinical examination had a sensitivity of 70.8%, specificity of 90.3%, positive predictive value of 85% and negative predictive value of 80%. The diagnosis of all the cases was not changed after ECG studies. However, on echocardiographic studies, a higher incidence of pathologic cardiac lesions [44% of cases] was identified, Echocardiography with colour doppler was found necessary in early diagnosis and management of suspected congenital heart disease in infancy even in a clinically diagnosed innocent systolic heart murmur

Dipyridamole thallium scintigraphy

Intravenous dipyridamole scintigraphy was performed in 100 cases with suspected or diagnostic coronary heart disease who were unable to exercise. Side effects were few of no clinical significance and disappeared following IV theophylline. Positive thallium scintigraphy was found in 55 cases, 31 had transient uptake defect, 17 had persistent defects and a combined uptake defects were present in 7 cases. The frequency of dipyridamole induced ST segment changes as well as the scintigraphic uptake defects were high in patients with history of typical anginal pain compared to those with atypical chest pain [p < 0.05, p < 0.05, respectively]. Persistent uptake defects diagnostic of myocardial infarction were found in 10 out of 14 patients [70%] in whom the diagnosis of myocardial infarction was inconclusive by history or electrocardiographic changes. Transient ischemic uptake defects were detected in 2 of 6 cases of recent MI [33%] and in 2 out of 9 cases of old MI [22%] denoting residual associated myocardial ischemia. Our study concluded that dipyridamole thallium scintigraphy imaging is a practically safe procedure. Its few side effects are reversible by IV theophylline. It provides a great diagnostic and prognostic value in patients with coronary artery unable to exercise and may thus serve as a useful alternative diagnostic modality to physical exercise

Data from lipid screening in private practice in Jeddah, Saudi Arabia

We screened 475 subjects for fasting serum total cholesterol and triglyceride. They included 315 males and 160 females. The age range was 10-70 years. The mean serum total cholesterol [STC] was 5.5 mmol/L +/- 1.5 [5.5 +/- 1.6 in males and 5.6 +/- 1.4 in females]. The mean value for serum triglyceride was [2.5 +/- 1.3 in males and 2.1 +/- 1.4 in females], STC was slightly higher in females than in males in all age groups up to the 3rd decade of life. 39% of the population group had STC less than 5.2 - 7.5 mmol/L and in 23% the level was higher than 7.5 mmol/L. Serum triglyceride was above 2.28 mmol/L in 33% of cases, a higher incidence was found among the elderly and the diabetics. In comparison to the data reported from other countries, we have shown that the mean STC in our selected population is in the intermediate nations. Health care measure should be undertaken to counteract the problem of dyslipidemia including public education, routine necessary dietary modification and encouragement of physical exercise

Aging and diastolic lv function[ ECHO/doppler study]

Echo-doppler parameters of left ventricular diastole were examined in 102 healthy subjects aged 1 month to 78 years who were clinically free and had normal M-Mode and 2 D echo. Early diastolic filling parameters included [E amplitude. E wave acceleration time and decerrelation time and time velocity integral of E wave [TIV] E. Late filling parameters included [A amplutide, E/A ratio and time velocity integral of A wave [TIV] A. The data obtained indicated [1] inital increase in the early filling parameters up to the second decade with maximum uprise rate during infancy [P<0.001]. This inital increase was followed by significant decrease afterwards to the elderly life [2] There was inital reduction of the late filling parameters of low statistical significance up to the second decade followed by a significant increase in the elderly subjects [P<0.001]. E/A ratio showed an inital increase followed by progressive reduction with aging [P<0.001]. [3] Comparison of age to [E amplitude, A amplitude and E/A ratio] revealed a linear relation of age to E amplitude [r=-0.70, P<0.001], to A amplitude [r=0.48, p<0.01] and to E/A ratio [r=-0.70. P<0.001]. In summary, Doppler LV diastolic parameter are altered significantly by aging. Early diastolic filling and ventricular inflow increased up to the 2nd decade, possibly due to an associated increase in the LV cavity, then progressively decreased with an associated increased late filling to compensate for decreased ventricular compliance. Aging is an independent determinate of most of the indices of LV diastolic flow and its effect should be taken into consideration for proper definition of the normal limit of the diastolic Doppler indices