Recurrent migration of peripherally inserted central catheter into the azygos vein

Peripherally inserted central catheter (PICC) migration into azygos vein (AV) is a rare complication. It is recognised only when catheter malfunction occurs or when patients develop associated complications. PICC migration into AV has been reported to be associated with various complications such as catheter malfunction, perforation, haemorrhage, thrombosis, infection and stenosis of AV. Pleural effusion and trachea-azygos fistulas have also been reported. We present a patient with recurrent migration of PICC into AV after an initial corrective repositioning during the same hospital stay. In this case, PICC migration was possibly related to left-sided approach, use of smaller diameter PICC, severe congestive heart failure and her bedbound status. PICC migration should be considered when PICC found be malfunctioning, especially if associated with the above risk factors

Genetic variation in SCN10A influences cardiac conduction

To identify genetic factors influencing cardiac conduction, we carried out a genome-wide association study of electrocardiographic time intervals in 6,543 Indian Asians. We identified association of a nonsynonymous SNP, rs6795970, in SCN10A (P = 2.8 x 10(-15)) with PR interval, a marker of cardiac atrioventricular conduction. Replication testing among 6,243 Indian Asians and 5,370 Europeans confirmed that rs6795970 (G>A) is associated with prolonged cardiac conduction (longer P-wave duration, PR interval and QRS duration, P = 10(-5) to 10(-20)). SCN10A encodes Na(V)1.8, a sodium channel. We show that SCN10A is expressed in mouse and human heart tissue and that PR interval is shorter in Scn10a(-/-) mice than in wild-type mice. We also find that rs6795970 is associated with a higher risk of heart block (P < 0.05) and a lower risk of ventricular fibrillation (P = 0.01). Our findings provide new insight into the pathogenesis of cardiac conduction, heart block and ventricular fibrillation