Iranian Heart Journal
Volume:16 Issue: 2, Summer 2015

There is some evidence that melatonin therapy may be of benefit to patients with the metabolic syndrome. This study was designed to find out whether the administration of melatonin before coronary angiography can decrease the stress-induced blood pressure increment. Patients referring for coronary angiography were randomized into 2 groups in this double- blind, randomized, clinical trial study. The study population consisted of 209 patients: 104 cases in Group A and 105 cases in Group B. The patients in Group A received 3 mg of controlled-releasing melatonin for 5 nights before angiography time and 5 mg of fast- releasing melatonin 1 hour before angiography. The patients in Group B received a placebo in the same way. We recorded the blood pressure and heart rate of the patients at admission to the ward (BP1 and HR1), at entrance in the catheterization laboratory (BP2 and HR2), after arterial puncture (BP3 and HR3), and—finally—before transfer to the ward (BP4 and BP4) and compared them between the 2 groups. The comparison of the recorded systolic and diastolic blood pressures and heart rates showed no statistically significant differences between the 2 groups. Our results showed that using melatonin as a premedication could not prevent stress- induced blood pressure elevation during selective coronary angiography in our study population.(

Serum B-type natriuretic peptide (BNP) and echocardiographic findings are among the invaluable tools to predict heart failure in cancer patients receiving chemotherapy. The aim of this study was to measure the serum BNP level and assess the echocardiographic findings of patients with malignancy treated by chemotherapy so as to find out any significant changes in the values of the mentioned indices. This cross-sectional study was performed on 40 consecutive cancer patients who received various chemotherapeutic regimens. Serum BNP levels were measured as well as echocardiographic evaluation by 2-dimensional and Doppler echocardiography (using a Vivid 3 instrument) at baseline (before administering chemotherapy) and at 3 and 6 months after chemotherapy. Echocardiographic indices included left ventricular ejection fraction (LVEF), fractional shortening, tricuspid annular plane systolic excursion (TAPSE), and left ventricular end-diastolic diameter (LVEDD). Eleven (27.5%) patients developed heart failure (ie, LVEF < 55%) at 6 months'' follow-up. The mean LVEF at baseline was 59.00% (± 3.62), which decreased to 55.58% (± 5.80) at 6 months (P < 0.001). The mean LVEDD at baseline was 53.70 (± 3.74), which significantly increased to 56.60 (± 5.30) 6 months after chemotherapy. The mean (SD) serum BNP level was 51.08 (± 22.51), which significantly increased to 95.80 (± 63.56) after 6 months (P < 0.001). The best cutoff point of BNP for discriminating heart failure from normal heart condition was 136.5 pg/mL, yielding sensitivity of 81.8% and specificity of 96.6%. Each of the parameters of LVEF, fractional shortening, TAPSE, LVEDD, and even serum level of BNP underwent deteriorating changes at 3 months after chemotherapy, indicating the early occurrence of heart failure in these patients. However, following these changes, compensatory systems can be activated to regulate these cardiac parameters.

Strain rate imaging (SRI) is a new diagnostic technique. We studied the role of SRI in patients suspected to have coronary artery disease. The aim of this study was to determine the diagnostic value of SRI for the detection and localization of coronary lesions in patients with chest pain but without apparent wall-motion abnormalities. We studied 91 patients with suspicion of stable angina or unstable angina. SRI using tissue Doppler imaging was conducted before coronary angiography. All the patients had normal electrocardiography and normal wall motion on echocardiography. Longitudinal strain was obtained for 18 segments in the left ventricle. We studied peak longitudinal strain (ԑsys) and post-systolic shortening (PSS) and its characteristics in normal and abnormal segments. Significant coronary lesion was considered if stenosis was above 70%. Forty patients with heterogeneity of strain and 2 patients with constant strain had significant coronary stenoses. Thirty-one patients with constant strain and 18 patients with heterogeneity of strain had normal or minimal coronary lesions. Furthermore, ԑsys was less in the ischemic segments than in the normal ones (P<0.001). The receiver operating characteristic (ROC) analysis for ԑsys yielded an area under curve (AUC) of 0.86 (95% CI, 0.84 to 0.88). A cutoff point of -11.4 had the most sensitivity and specificity (69.55% and 87.23%, respectively). PSS was more frequent in the ischemic segments than in the normal ones (64.5% vs 22.6%; P<0.001). The magnitudes of ԑpss, ԑpss/ԑsys (PSI), and ԑpss/ԑmax were significantly larger in the ischemic segments (P<0.001), and T ԑpss was longer (P <0.001). SRI is a new noninvasive diagnostic tool that can be used to detect coronary stenosis in patients with chest pain but without apparent wall-motion abnormalities on echocardiography.

To assess changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) following exercise training, we evaluated the changes in the circulating NT-proBNP level after diagnostic exercise testing in patients with suspected coronary artery disease (CAD). Twenty patients with chest pain and clinical suspicion of CAD were recruited as the case group, and from among those scheduled for the exercise test without any clinical evidence of cardiovascular disease, 20 were randomly selected as the control group. In both groups, an exercise test was conducted according to the Bruce Protocol. The NT-proBNP level was measured with the Roche Diagnostics kits and electrochemiluminescence immunoassay immediately before and also 2 to 5 minutes after exercise testing. The severity of coronary artery stenosis was presented by the number of significant stenotic vessels according to coronary angiography. The mean levels of the pre- and post-exercise test NT-proBNP levels were significantly higher in the case group. Also, in both groups, the plasma BNP was significantly increased after the exercise test; however, the change in the NT-proBNP level was significantly higher in the former group (ΔBNP, 103.08 ± 57.54 pg/mL vs 4.24 ± 5.46 pg/mL; P < 0.001). There was a positive relation between the number of the involved coronaries and changes in the NT-proBNP concentration (ΔBNP, 34.37 ± 23.59 pg/mL for the normal coronary group, 102.87 ± 32.06 pg/mL for the single-vessel disease group, 113.50 ± 17.25 pg/mL for the 2-vessel disease group, and 146.64 ± 39.00 pg/mL for the 3-vessel disease group; P < 0.001). Multivariable linear regression analysis showed that among the different study indicators, only CAD severity was strongly associated with the changes in the plasma NT-proBNP level after the exercise test (β, 31.10; SE, 5.16; P < 0.001). The NT-proBNP level was increased after the exercise test both in the patients with suspected CAD and in the healthy controls. However, the elevation in the NT-proBNP level was notably higher in the former group. The change in the NT-proBNP following the exercise test was strongly able to predict the severity of the involvement of the coronary arteries.

The role of polymorphisms on the sequences of the endothelial nitric oxide synthase (eNOS) gene has been proposed to predispose coronary artery disease patients to stent restenosis. We conducted the present study to examine the involvement of the role of the -786T>C variant of the eNOS gene in stent restenosis following coronary stent deployment. This cross-sectional study was conducted on 100 consecutive patients who underwent coronary stenting. The study population was assigned into a case group, who had restenosis and were candidated for revascularization (n, 50), and a matched control group, who underwent coronary stenting but without evidence of restenosis within 6 months of stenting (n, 50). The -786T>C polymorphism was identified, following polymerase chain reaction (PCR), by restriction enzyme digestion. The overall prevalence of restenosis was 34.4%. In total, the frequency of the wild genotype (CC) of the -786T>C variant was 41.9%, the frequency of heterozygous genotype (TC) was 41.9%, and the frequency of the mutant genotype (TT) was 40.9%. We found an association between the presence of stent restenosis and the presence of the -786T>C variant: in the patients with and without restenosis, the frequency of the CC genotype was 24.2% and 51.7%, the frequency of the TC genotype was 12.1% and 20.0%, and the frequency of the TT genotype was 63.6% and 28.3%, respectively (P = 0.023). In the multivariate logistic regression analysis, along with the presence of the -786T>C variant, the other determinants of stent restenosis included male gender, waist circumference, both systolic and diastolic blood pressures, history of dyslipidemia, left anterior descending artery (LAD) involvement, distal position of stenting, and duration of the concomitant use of aspirin and Plavix®. However, in similar analysis, none of the pointed factors could predict the severity and percentage of restenosis. The presence of the -786T>C polymorphism of the eNOS gene is a major and serious risk factor for stent restenosis, independent of the effects of other cardiovascular risk factors. The effect of this polymorphism is particularly highlighted in the LAD. Nevertheless, it seems that the -786T>C polymorphism may not have a central role in the progression and severity of stent restenosis.

The development of instrument engineering in the field of cardiology research and observations was started in the late twentieth century. This purpose in view is achieved by correct problem setting and solving in the development of new algorithms for the analysis of body parameters (including electrical signals) and implementation of these algorithms in software environment for the implementation end in the device.

The method of heart rate variability (HRV) analysis, allowing to accumulate and identify rare and sudden changes in patient status with ventricular heart rhythm disorders, was externalized by the creation of hardware-software complex (HSC) presented in this study. The main feature of this method is the presence of a special module in the construction of the temporary pacemaker realizing diagnostic data passing for further HRV analysis and observing a module that consists of an analog-to-digital converter (ADC), microcontroller, and USB port. The HSC is presented by the signal processing module (analysing nerve cell spikes in the heart’s ventricle). The purpose of the study was to assess HRV in the pathology of the ventricular activity. Therefore, the pacemaker electrode was located in the apex of the right ventricle, and the electrical activity of the right ventricle was analyzed.

This study presents the results of the implementation of the HRV analysis of the signals received from the apex of the ventricle of patients with ventricular heart rhythm disorders and offers meaningful graphical interpretations of the results.

In conclusion, the present study contains the implementation of HRV assessment modes for the signals received during pacing from the ventricular apices in patients with ventricular rhythm disorders and substantial graphic interpretation of the results.

Case Report: We describe a 40-year-old male who was brought to our hospital with venous thrombosis 6 hours after a snakebite. The patient had local envenomation with blindness. Magnetic resonance imaging of the brain showed infarct in the posterior circulation. The neurological manifestations following snakebite are often due to hemorrhagic complications. Presentation with infarction is rare and can be attributed to vasculitis, vasospasm, endothelial damage, toxin-induced procoagulant effect, and disseminated intravascular coagulation.