Interatrial Block in the Modern Era

Interatrial block (IAB; P-wave duration ≥ 110 ms), which represents a delay in the conduction between the atria, is a pandemic conduction abnormality that is frequently underappreciated in clinical practice. Despite its comprehensive documentation in the medical literature, it has still not received adequate attention and also not adequately described and discussed in most cardiology textbooks. IAB can be of varying degrees and classified based on the degree of P-duration and its morphology. It can transform into a higher degree block and can also manifest transiently. IAB may be a preceding or causative risk factor for various atrial arrhythmias (esp. atrial fibrillation) and also be associated with various other clinical abnormalities ranging from left atrial dilation and thromboembolism including embolic stroke and mesenteric ischemia. IAB certainly deserves more attention and prospective studies are needed to formulate a standard consensus regarding appropriate management strategies.     

Prevention of Kernicterus in South Asia: Role of Neonatal G6PD Deficiency and its Identification

Extreme hyperbilirubinemia (EHB) caused by neonatal glucose-6-phosphate dehydrogenase (G6PD) deficiency is strongly associated with mortality and long-term neurodevelopmental impairment, yet there are limited national strategies to reduce this burden in South Asia. Current known and predicted prevalence of G6PD deficiency in Afghanistan, Bangladesh, Bhutan, India, Nepal, and Pakistan ranges from 3.8 to 15 %, with regional “hot spots” exceeding 22 %. Annually, 3.14 million infants are born at risk for this condition. In 2010, South Asian countries reported 37 million (27 %) of world-wide livebirths ≥ 32 wk gestational-age and G6PD deficiency accounted for > 33 % of the global EHB burden, in contrast to 2.2 % for those born in high-income nations. Traditional national approach includes universal newborn screening in malaria-endemic countries or those with prevalence >3.5 %. However, screening implementation should be best optimized using timely quantitative enzyme assay and identification of at-risk female newborns. Furthermore, economic and social constraints, in context of sub-regional variances, call for flexible problem-solving methods in anticipation of changing community demographics. Thus, incremental and need-based newborn screening programs could be the most optimal approach. A human-centered design (HCD) approach, as an alternate pathway, could build the evidence to translate the complex biology of G6PD deficiency and the biodesign of affordable technologies, allowing facilitation of access to knowledge and services, in order to deliver on a long-term public health mandate. Key steps would encompass the initiation of local inquiry of both quantitative and qualitative data to identify at-risk communities and to prospectively design for local innovative solutions.     

Reappraisal of the effectiveness of methotrexate in psoriatic arthritis: results from a longitudinal observational cohort

OBJECTIVE: In a previous study in our clinic, methotrexate (MTX) conferred no advantage with respect to clinical response or progression of damage after 24 months in patients with psoriatic arthritis (PsA). Our aim was to determine if MTX is being used earlier in the course of PsA and in a higher dose and whether that has led to improved outcomes. METHODS: All patients treated with MTX for at least 24 months in our clinic, between 1994 and 2004, were included in the study. The outcome measures were the progression of radiographic peripheral joint damage score and a > or = 40% reduction in the number of actively inflamed joints. The data from our study were compared to those obtained from our previous study. RESULTS: Fifty-nine patients (36 men) treated with MTX for 24 months were identified. The mean age was 46 years, PsA duration 8 years, and active joint count 12.1 (4.6 swollen). The mean increase in radiographic damage score was 1.5. Sixty-eight percent of patients demonstrated improvement at 24 months. When compared to our previous study, there was a trend for MTX to be used earlier, at a higher dose, with greater clinical improvement and less progression of damage. CONCLUSION: Our study suggests that treatment with MTX has changed in the past decade to include patients with shorter disease duration and less damage, at increased dose, and that there may be better response with less progression of damage.     

Observation of thoracic duct morphology in portal hypertension by endoscopic ultrasound

Background:Thoracic duct dilation has been demonstrated in portal hypertension and hepatic cirrhosis by lymphangiography and laparotomy and at autopsy. It is thought to be secondary to increased hepatic lymph flow and has been described in the absence of ascites or esophageal varices. The aim of the present study was to observe thoracic duct morphology by endoscopic ultrasound in various subsets of patients with portal hypertension and hepatic cirrhosis and also to validate existing radiologic/surgical data. Methods:The thoracic duct of 33 patients with cirrhosis and portal hypertension was studied by endoscopic ultrasound. Patients were divided into four groups: 1, patients with ascites and esophageal varices; 2, esophageal varices without ascites; 3, without esophageal varices or ascites; 4, extrahepatic portal hypertension due to pancreatic malignancy. The thoracic duct diameter was also measured in 14 control subjects (group 5). Results:When the thoracic duct diameter for the five groups was compared with analysis of variance, significance was p < 0.0001; by pairwise comparison, group 1 differed from the other four groups (p < 0.05). Thoracic duct dilation (5.61 mm) was seen in group 1 patients, whereas no dilation was present in groups 2 through 4. Additionally, thoracic duct diameter in 33 portal hypertensive and/or cirrhotic patients was significantly different from that in the 14 control subjects (p = 0.003). Conclusion:The thoracic duct can be reliably identified by EUS in patients with hepatic cirrhosis and portal hypertension. Dilation of the duct is seen only in patients with hepatic cirrhosis, ascites, and esophageal varices. No thoracic duct dilation is present in extrahepatic portal hypertension. Contrary to existing radiologic/surgical data, thoracic duct dilation is not seen in all patients with hepatic cirrhosis and portal hypertension signifying advanced disease. A dilated thoracic duct by endoscopic ultrasound should be considered yet another sign of portal hypertension. (Gastrointest Endosc 1998;48:588-92.)