Assessment of corrected QT interval in sickle cell disease patients who undergo erythroapheresis

Abstract

Extension of the QT interval is characterized by syncope and cardiac arrest and often occurs in association with medical therapies and procedures. Whether erythroapheresis (EPH) could influence the QT interval duration in patients with sickle cell disease (SCD) is not known. We aimed to investigate the effects of EPH on the heart rate-corrected QT (QTc) interval. The study included 25 patients with SCD who underwent 34 EPH procedures. Two independent observers measured QTc interval duration from electrocardiograms performed continuously for 3 min at three different points during the EPH procedures (prior to EPH, after completion of 50% EPH and 15 min after EPH). Multiple regression analysis was used to determine if the ionized plasma calcium, the level of plasma magnesium, citrate infusion rate and painful crisis significantly contributed to the QTc interval. There was a non-significant trend (P = 0.184) towards increased QTc in sickle cell patients during EPH compared with pre-EPH values. QTc prolongation (>440 ms) occurred in 72% of the procedures. Fifty percent QTc values returned to baseline after the procedure. The independent variables were not significantly associated with QTc interval. Exchange procedures can induce QTc prolongation in patients with SCD.

Prophylactic red blood cell exchange may be beneficial in the management of sickle cell disease in pregnancy

“…Our study patients had end organ failures before pregnancy and they were admitted to hospital several times due to causes like painful vasoocclusive crises (n = 24), recurrent infections (n = 20), acute chest syndrome (n = 5), leg ulcers (n = 6), hepatic necrosis (n = 1), neurologic events (n = 2), and bone necrosis (n = 2) so they had undergone RBCX procedures. Our previous clinic experience also shows that automated RBCX is an effective and safe procedure in patients with SCD . Considering the aforementioned issues, we established a policy to perform RBCX for management of SCD patients during pregnancy.…”

“…Pregnant patients with SCD require close surveillance by multidisciplinary teams, which should include hematologists, obstetricians, anesthetists, and pediatricians who are experienced in the management of this disorder. Our team manages adult sickle cell patients and has great experience as we have been performing RBCX procedure for more than 10 years to treat severe cases of SCD …”

Cardiac autonomic dysfunction in sickle cell anaemia and its correlation with QT parameters

“…This is due to prolongation and inhomogeneity of ventricular repolarisation which is a harbinger for arrhythmias. Similarly, some studies have associated QTc prolongation and QTcd to pulmonary hypertension and chronic transfusion which are common in SCA 92223…”

QTc prolongation during peripheral stem cell apheresis in healthy volunteers

“…Citrate infusion has also been associated with reduced myocardial contractility, a fall in pulse pressure, reduced cardiac output, and even cardiac arrest. The most common effect of hypocalcemia evident on an electrocardiogram (ECG) is QTc prolongation . The QT interval represents the time from the onset of ventricular depolarization to the end of repolarization.…”

“…A surface ECG measures the time from the onset of the Q wave to the end of the T wave. The QT interval varies by heart rate and must be appropriately corrected . Of the several methods of correction available, Bazzett's formula is commonly used .…”