Ventricular arrhythmia is predicted by sum absolute QRST integralbut not by QRS width

Background

There is a controversy regarding the association between QRS width and ventricular arrhythmias (VAs). We hypothesized that predictive value of the QRS width could be improved if QRS width were considered in the context of the sum magnitude of the absolute QRST integral in 3 orthogonal leads sum absolute QRST integral (SAI QRST). We explored correlations between QRS width, SAI QRST, and VA in primary prevention implantable cardioverter-defibrillator (ICD) patients with structural heart disease.

Methods

Baseline orthogonal electrocardiograms were recorded at rest in 355 patients with implanted primary prevention ICDs (mean age, 59.5 ± 12.4 years; 279 male [79%]). Patients were observed prospectively at least 6 months; appropriate ICD therapies because of sustained VA served as end points. The sum magnitude of the absolute QRST integral in 3 orthogonal leads (SAI QRST) was calculated.

Results

During a mean follow-up of 18 months, 48 patients had sustained VA and received appropriate ICD therapies. There was no difference in baseline QRS width between patients with and those without arrhythmia (114.9 ± 32.8 vs 108.9 ± 24.7 milliseconds; P = .230). SAI QRST was significantly lower in patients with VA at follow-up than in patients without VA (102.6 ± 27.6 vs 112.0 ± 31.9 mV·ms; P = 0.034). Patients with SAI QRST (≤145 mV·ms) had a 3-fold higher risk of ventricular tachycardia (VT)/ventricular fibrillation (VF) (hazard ratio [HR], 3.25; 95% confidence interval [CI], 1.59-6.75; P = .001). In the univariate analysis, QRS width did not predict VT/VF. In the bivariate Cox regression model, every 1 millisecond of incremental QRS widening with a simultaneous 1 mV·ms SAI QRST decrease raised the risk of VT/VF by 2% (HR, 1.02; 95% CI, 1.01-1.03; P = .005).

Conclusion

QRS widening is associated with ventricular tachyarrhythmia only if accompanied by low SAI QRST.     

Hepatic Arterial Infusion of Oxaliplatin and Intravenous LV5FU2 in Unresectable Liver Metastases from Colorectal Cancer after Systemic Chemotherapy Failure

Background We have previously shown promising activity of hepatic arterial infusion (HAI) oxaliplatin combined with intravenous (IV) 5-fluorouracil (5-FU) and leucovorin (LV) as first-line chemotherapy in patients with colorectal liver metastases (CRLM) (intent-to-treat [ITT] objective response rate [ORR], 64%; secondary resection rate, 18%; overall survival [OS], 27 months). Whether this regimen could be beneficial after systemic chemotherapy failure is unknown. Methods Patients with unresectable CRLM and history of systemic chemotherapy failure were treated bimonthly with HAI oxaliplatin (100 mg/m² 2 hours) combined with IV LV and IV bolus and infusional 5FU (modified LV5FU2 regimen). Results Forty-four consecutive patients (median age 56 years; median number of prior systemic chemotherapy regimens, 2 range 1–5) were included, of whom 43 (98%) had previously received oxaliplatin (n = 34), irinotecan (n = 37), or both (n = 28). Patients received a median of nine cycles of HAI oxaliplatin and IV modified LV5FU2 (range 0–25). Toxicity included grade 3–4 neutropenia (43%), grade 2–3 neuropathy (43%), and grade 3–4 abdominal pain (14%). We observed 24 partial ORs (62%) among the 39 assessable patients (ITT ORR, 55%; 95% CI, 40–69%), including 17, 12, and 12 patients who had failed to respond to prior systemic chemotherapy with FOLFIRI, FOLFOX, or both, respectively. Tumor response allowed further R0 surgical resection (n = 7) or radiofrequency ablation (n = 1) of initially unresectable CRLM in eight patients (18%). Median progression-free survival and OS were 7 and 16 months, respectively. Conclusions HAI oxaliplatin and IV LV5FU2 is feasible, safe, and shows promising activity after systemic chemotherapy failure, allowing surgical resection of initially unresectable CRLM in 18% of patients.     

Toward an easier indigocarmine chromoendoscopy

Indigocarmine chromoendoscopy has been proven to improve the detection of colonic lesions during screening colonoscopy, and is associated with increased adenoma detection rates. Furthermore, it is commonly used to help in the delineation and characterization of colorectal neoplasms. However, it usually requires the use of a spraying catheter that decreases the suction capacity of the endoscope, and is time- consuming. Herein, we report on the feasibility of indigo carmine chromoendoscopy during colonoscopy without using a spraying catheter, with the dye being administered through the air/water channel of the endoscope. Since the suction channel remains free, the air can be exsufflated and the staining then applies uniformly onto the colonic walls with the excess indigocarmine dye being immediately eliminated. In our experience with various types of colonoscopes and cap-assisted colonoscopy, this procedure makes indigocarmine chromoendoscopy much easier and quicker to perform, and might save the use of a spray catheter.