Study of pattern & distribution of adverse drug reactions in acute coronary syndrome patients in a tertiary care hospital

Background & objectives: With the availability of a wide range of drugs to treat patients with acute coronary syndrome (ACS), adverse drug reactions (ADRs) have become inevitable in clinical practice. Thorough knowledge of such reactions is essential for the treating physician for optimal treatment and better outcomes. There are many scales to define, measure and assess the ADRs, but there is a dearth of data available on such drug reactions among ACS patients. Hence, this study attempted to analyze the pattern, causality, severity, predictability and preventability of ADRs in ACS patients. All the ADRs reported during the study period were analyzed for causality by the World Health Organization–Uppsala Monitoring Centre (WHO-UMC), Naranjo’s and Karch and Lasagna scales; severity by modified Hartwig and Siegel scale; predictability by Rawlins and Thompson criterion and preventability by Schumock and Thornton scale. Methods: A single-centre, record-based analysis for the occurrence of ADRs was done among ACS patients admitted to the department of Cardiology between January and October 2017. Demographic data, comorbid conditions, reported ADRs and ADR assessment details were noted from the hospital case records and ADR monitoring centre (AMC) records. The data were analyzed and presented in a descriptive manner using percentages, mean and standard deviation. The Pearson’s chi-squared test was used to ascertain the significance of the association between different groups. Results: Out of 324 patients under evaluation, 67 had developed one or more ADRs. There were 30 different types of ADRs reported, headache being the most common. Among the drugs, heparin was the most common factor, causing 27 per cent of ADRs. Definite causality of a suspected drug causing ADRs was seen in 11.9 (n=8), nine (n=6) and 7.5 (n=5) per cent cases as per WHO-UMC, Naranjo (Naranjo algorithm) and Karch and Lasagna scales, respectively. In the severity of ADRs, the most severe reactions according to the modified Hartwig-Siegel scale (level 4a in our study) were seen in 17.5 (n=12) per cent of patients, and the rest were either level 2 or 3 reactions. Nearly 92.5 (n=62) per cent of reactions were predictable according to the Rawlins and Thompson criterion. Application of the modified Schumock-Thornton scale showed that 22.4 per cent of ACS patients had preventable reactions, and the rest were not preventable.Interpretation & conclusions: The study results suggest that ADRs are relatively common among ACS patients. Most of these can be identified and assessed for causality, severity, predictability and preventability using various available scales. Diligent pharmacovigilance for identifying and assessing ADRs may help manage and mitigate morbidity associated with these in high-risk ACS patients.

Incidence and predictors of perioperative myocardial infarction in patients undergoing non-cardiac surgery in a tertiary care hospital

Background The stress in the perioperative period is compounded by unpredictable and un-physiological changes in sympathetic tone, cardiovascular performance, coagulation and inflammatory responses, all of which in turn lead to alterations in plaque morphology predisposing to perioperative myocardial infarction (PMI). PMI has a considerable morbidity and mortality in patients undergoing not only high risk surgery, but also even with minor surgical interventions. Objective To study the incidence of PMI and its predictors in patients undergoing non-cardiac surgery in a tertiary care hospital. Materials and methods Patients undergoing non-cardiac surgery were included in this prospective single-center observational study. The revised cardiac risk index (RCRI) was used for risk stratification. ECG monitoring was done for all patients. For patients suggestive of acute myocardial ischemia, echocardiography and serum troponin were evaluated. The patient was labeled as having a PMI if there was raised troponin level along with any one evidence of myocardial ischemia (symptoms, ECG changes or imaging results) and in these patients the factors predisposing to PMI were evaluated. All patients in the study were followed up to 30 days. Results Of the 525 patients analyzed, 33 patients (6.28%) had a PMI. Twelve out of the 33 (36.36%) PMI patients died within 30 days following surgery. Patients undergoing high risk surgery, smokers and patients with a past history of ischemic heart disease (IHD) were found to be at higher risk of developing PMI. The ASA physical status classification and the RCRI proved to be good predictors of PMI. Most of the PMI events (72.7%) occurred within 48 hours of surgery. Conclusion PMI is a dreaded complication associated with a very high mortality. High risk surgery, smoking and past history of ischemic heart disease were independent predictors of PMI. The RCRI is a useful tool in pre-operative risk stratification of patients.

Evaluation for airway obstruction in adult patients with stable ischemic heart disease

Background Ischemic heart disease (IHD) and chronic airway disease (COPD and Asthma) are major epidemics accounting for significant mortality and morbidity. The combination presents many diagnostic challenges. Clinical symptoms and signs frequently overlap. There is a need for airway evaluation in these patients to plan appropriate management. Methods Consecutive stable IHD patients attending the cardiology OPD in a tertiary care centre were interviewed for collecting basic demographic information, brief medical, occupational, personal history and risk factors for coronary artery disease and airway disease, modified medical research centre (MMRC) grade for dyspnea, quality of life-St. George respiratory questionnaire (SGRQ), spirometry and six-min walk tests. Patients with chronic airway obstruction were treated as per guidelines and were followed up at 3rd month with spirometry, six-minute walk test and SGRQ. Results One hundred fourteen consecutive patients with stable cardiac disease were included (Males-88, Females-26). Mean age was 58.89 ± 12.24 years, 53.50% were smokers, 31.56% were alcoholics, 40.35% diabetics, 47.36% hypertensive. Twenty five patients had airway obstruction on spirometry (COPD-13 and Asthma-12) and none were on treatment. Thirty-one patients had cough and 48 patients had dyspnea. Patients with abnormal spirometry had higher symptoms, lower exercise tolerance and quality of life. Treatment with appropriate respiratory medications resulted in increase in lung function, quality of life and exercise tolerance at 3rd month. Conclusion Chronic respiratory disease in patients with stable IHD is frequent but often missed due to overlap of symptoms. Spirometry is a simple tool to recognize the underlying pulmonary condition and patients respond favorably with appropriate treatment

Regional differences in the reference blood pressure in young Indians.

This study compares the blood pressure (BP) in young population of North India and South India. Age, height and sex specific BP was estimated for 6320 North Indian subjects aged 7-18 years and compared with BP values of South Indian subjects. North Indian boys and girls had lower diastolic BP (DBP) with no difference in systolic BP (SBP) than South Indian boys and girls between 7-12 years. Between 13-18 years North Indian boys and girls had significantly higher SBP with no difference in DBP. The significant regional differences in BP distribution among young Indians suggest considering geographic location of the population in evaluating blood pressure.

Blood pressure reference tables for children and adolescents of Karnataka.

BACKGROUND: The blood pressure levels may vary in population because of genetic, ethnic and socio economic factors. Local reference values have to be established to understand the blood pressure variable. METHODS: Blood pressure data of 2278 boys and 2930 girls in the age group of 3-18 years were analysed to study the distribution pattern of systolic blood pressure and diastolic blood pressure and to develop reference values to define hypertension. Blood pressure was measured using standardised techniques in all. The first and fifth phases of Korotkoff sounds were taken as indicative of systolic blood pressure and diastolic blood pressure respectively. Height percentiles were computed for each one year age group. According to percentiles of height 50th, 90th, 95th and 99th percentiles of systolic blood pressure and diastolic blood pressure were estimated for every one year age. RESULTS: The blood pressure (both systolic and diastolic) tends to increase with age. The stepwise regression analysis revealed that the age and height but not gender, are important determinants of blood pressure. Age and height specific, 50th, 90th and 95th and 99th percentiles of systolic and diastolic blood pressure were derived and are presented in tabular form. CONCLUSION: The blood pressure of children and adolescents can be evaluated using the reference table according to body size. The table provided helps to classify blood pressure as normal or pre hypertension and to define different stages of hypertension.

Effect of mechanical coronary reperfusion on QT dispersion in acute coronary syndrome.

BACKGROUND: The time for cardiac repolarization and homogeneity of repolarization on surface electrocardiogram is denoted by QT interval and QT dispersion, respectively. Numerous studies suggest an association between an increased dispersion of the QT interval obtained from the 12-lead electrocardiogram and increased risk for serious cardiac events. METHODS AND RESULTS: We evaluated the effect of thrombolysis and percutaneous transluminal coronary angioplasty on QT dispersion in acute coronary syndrome in 45 patients (age: 55 +/- 6 years). QT dispersion was calculated on admission and immediately after the procedure (thrombolysis and percutaneous transluminal coronary angioplasty). There was a significant decrease in QT dispersion after percutaneous transluminal coronary angioplasty (75 +/- 21 ms to 38 +/- 20 ms, p < 0.0001). In a subset of these patients with acute myocardial infarction (n = 29) who underwent thrombolysis, QT dispersion decreased only marginally (78 +/- 19 ms to 67 +/- 22 ms, p < 0.05). Even in this subgroup, there was a significant decrease in QT dispersion after percutaneous transluminal coronary angioplasty (to 37 +/- 22 ms, p < 0.0001). In patients with unstable angina (n = 16), there were similar significant changes after percutaneous transluminal coronary angioplasty (p < 0.0001). CONCLUSIONS: These results suggest a highly significant decrease in QT dispersion after percutaneous transluminal coronary angioplasty compared to a less significant decrease after thrombolysis, which may have clinical implications.

Increased beat-to-beat QT variability in patients with congestive cardiac failure.

BACKGROUND: QT interval on the surface electrocardiogram reflects the time for repolarization of myocardium. Prolongation of rate-corrected QT interval, QTc is strongly associated with sudden cardiac death. Recent studies using novel techniques on beat-to-beat QT interval variability have shown that an increase in QT interval variability is associated with increased sympathetic activity and is a predictor of sudden cardiac death. We studied QT variability in patients with congestive cardiac failure, as it is associated with an increase in cardiac sympathetic activity and also sudden death. METHODS AND RESULTS: We compared beat-to-beat heart rate and QT interval data in 2 3 patients with congestive cardiac failure and 19 age-matched normal controls. The electrocardiographic data were acquired in lead II configuration at a sampling rate of 1000 Hz. Heart rate variability was found to be significantly lower while QT variability measures were significantly higher in patients compared to controls. QTvi (a common log ratio of QT variability normalized for mean QT interval squared divided by heart rate variability normalized for mean heart rate squared) was also significantly higher in patients compared to controls. Clinical improvement in some of these patients is associated with a decrease in QTvi, due mainly to an increase in cardiac vagal function. CONCLUSIONS: Our results suggest a decrease in cardiac vagal and an increase in cardiac sympathetic functions in patients with congestive cardiac failure. QTvi may prove to be a useful surrogate end point to evaluate treatment effect in these patients.