Reciprocal ST-Segment Changes in Myocardial Infarction: Ischemia at Distance Versus Mirror Reflection of ST-Elevation.

BACKGROUND: Reciprocal ST-depression in the electrocardiograms (ECGs) of patients with ST-elevation myocardial infarction (STEMI) results from either true ischemia at a distance via collateral circulation diverting blood to the infarcted region or an electrical phenomenon that results from a mirror reflection of ST-elevation. We aimed to identify the role of reciprocal ECG changes in predicting collateral circulation to the infarcted area determined angiographically. METHODS: In a retrospective study, ECG and angiography of 53 STEMI patients admitted to SUNY Upstate Medical University in 2014 were reviewed independently by experts blinded to the results of ECG and coronary angiography. RESULTS: Reciprocal changes (RC) in ECG were present in 41 patients (77%) and on angiography, 14 patients (26%) exhibited collateral vessels to the ischemic areas. No correlation was found between the presence of RC and collateral circulation (P = 0.384), or between the depth of reciprocal ST-depression and the degree of the collateral circulation (P = 0.195). However, 84% of patients without collaterals exhibited resolution of RC after successful percutaneous coronary intervention (PCI) (P = 0.036), suggesting that the ST depressions that resolved after reperfusion were directly caused by the culprit vessel. Patients without RC presented late after symptom onset (9.25 versus 3.83 hours, P = 0.004), also suggesting time related resolution. CONCLUSIONS: RC had no relation to or predictive value for collaterals on angiography. Among late presenting patients, RC were less frequent. Thus, reciprocal ST-depression may represent subendocardial ischemia from the primary coronary event or simply an electrical phenomenon, rather than ischemia at distance from impaired collateral circulation.

Free phenytoin toxicity.

Phenytoin has a narrow therapeutic window, and when managing cases of toxicity, clinicians are very wary of this fact. Typically, if patient presents with symptoms suggestive of phenytoin toxicity, total serum phenytoin is promptly ordered. That could be falsely low especially in elderly or critically ill patients, which may lead to a low albumin level resulting in this discrepancy. The free phenytoin can be best estimated using the Sheiner-Tozer equation. Herein, we describe a case of an elderly male patient who presented with drowsiness, gait changes, and elevated liver enzymes and a normal total serum phenytoin level of 18 ng/dL (normal, 10-20 ng/dL).After taking his albumin level into account, his free phenytoin level was calculated to be 27 ng/dL, and the phenytoin was discontinued leading to resolution of his symptoms as well as a return of his liver function panel values to baseline.

Negative anion gap metabolic acidosis in salicylate overdose--a zebra!

Salicylate poisoning classically results in an increased anion gap metabolic acidosis. We discuss a case of normal anion gap metabolic acidosis despite elevated serum salicylate concentration. This diagnostic dilemma stemmed from aberrant reading of salicylate ions by analyzer electrodes as chloride ions leading to falsely negative anion gap. On review, this phenomenon is found to be possible with a number of commonly used analyzers. In emergency department settings, high level of clinical suspicion for salicylate poisoning should be maintained, and metabolic acidosis with normal anion gap should not be used to rule out salicylate overdose. This can prevent significant avoidable morbidity and mortality.

Effect of percutaneous mitral vavuloplasty on pregnant mother and foetus--a tertiary care hospital experience from a developing country.

UNLABELLED: This study evaluated the short and long-term consequences of Percutaneous Mitral Valvuloplasty (PMV) in pregnant patients and their offspring, in a tertiary care setting, Karachi, Pakistan. The hospital database was used to retrieve all patients who underwent PMV during pregnancy in the period 1998-2007. The follow up data of the patients and the born children were obtained from the hospital records and also by contacting the patients via phone. Six patients underwent PMV but follow-up was available for 5 patients only. All 5 patients were admitted due to severe mitral stenosis with symptoms of dyspnea and palpitation. Mean age was 27 +/- 5.3 years with a mean gestational age at the time of procedure of 22.20 +/- 1.6 weeks. The mean valve area increased from 0.94 +/- 0.22 cm2 preoperatively to 1.62 +/- 0.50 cm2 post-operatively. The ejection fraction changed from a mean of 50 +/- 11.7% to 56 +/- 2.2%. There were no maternal deaths, abortions or stillbirths. Developmental milestones were achieved at the appropriate ages in all babies. PMV appears to be a safe and effective intervention for patients with severe MS during pregnancy. KEYWORDS: Mitral stenosis, Percutaneous Mitral

The constant threat of terrorism: stress levels and coping strategies amongst university students of Karachi.

OBJECTIVES: To assess the levels of stress in the face of terrorism and the adopted coping strategies, amongst the student population of universities in Karachi. METHODS: A descriptive, cross sectional study was conducted on undergraduate students from four universities of Karachi. Self-administered questionnaires were filled out by 291 students. Pearson Chi-Square test was used to assess associations between stress levels and different variables at a level of significance of 0.05%. RESULTS: A total of 65.8% of the students had mild stress levels, 91.5% of university students were exposed to terrorism through television, while only 26.5% students reported personal exposure to terrorism. 67.4% students were forbidden by their parents to go out (p = 0.002). Most of those who had self exposure to an attack were the ones whose parents forbade them from going out (p = 0.00). Most commonly used coping strategy was increased faith in religion. Irritability was the most common stress symptom. CONCLUSION: A majority of students studying in universities of Karachi had mild stress levels due to the constant threat of terrorism whereas a minority had severe stress levels. Possible reasons for resilience and only mild stress levels could be the history of Karachi's internal conflicts and its prolonged duration of being exposed to terrorism. These students who are positive for stress need to be targeted for counseling either through the media or through their universities. More extensive research is needed in this area.