The American journal of cardiology
-
Prolonged and labile ventricular repolarization and decreased heart rate variability may be associated with susceptibility to ventricular fibrillation (VF) after myocardial infarction (MI). The response of ventricular repolarization related to abrupt heart rate changes may also be associated with arrhythmia vulnerability. We investigated whether diurnal maximal values or changing capacities of QT and T-wave peak to T-wave end (TPE) intervals are different in patients after MI with and without a history of VF. ⋯ Capacity to change QT and TPE intervals correlated with vagally mediated measurements of heart rate variability (r from 0.35 to 0.46, p from 0.01 to <0.001, respectively). In conclusion, long maximal QT interval may not be the key factor exposing patients after MI to VF. Impaired capacity to change QT and TPE intervals seems to be associated with risk of VF after MI.
-
Overlapping homogenous drug-eluting stents (DESs) may be used instead of overlapping bare metal stents (BMSs) to treat coronary lesions longer than available stents. Yet, no data are available on patients treated with overlapping heterogenous DESs or DESs and BMSs. We prospectively assessed 9-month clinical outcome and 6-month angiographic late loss (evaluated at 5 different lesion segments) in a consecutive series of 40 patients who received overlapping homogenous DESs (sirolimus-eluting stent [SES] or paclitaxel-eluting stent [PES]), heterogenous DESs (SES + PES), or overlapping DESs and BMSs. ⋯ Late lumen loss at the site of stent overlap showed significant differences according to type of overlapped stent (1.00 +/- 0.76 mm in DES-BMS overlap, 0.32 +/- 0.55 mm in PES-PES overlap, 0.13 +/- 0.11 in SES-PES overlap, and 0.08 +/- 0.10 mm in SES-SES overlap, p = 0.005). In conclusion, the present study suggests that overlap of DESs and BMSs should be avoided because the antirestenotic effect of DESs is skewed by contiguous BMS implantation. Overlap between SESs and PESs in this very preliminary report was associated with no specific adverse event.
-
Peak oxygen consumption (VO2) is a powerful prognostic predictor of survival in patients with heart failure (HF) because it provides an indirect assessment of a patient's ability to increase cardiac output (CO). However, many peripheral factors affect VO2. Inert gas rebreathing using low-concentration soluble and insoluble inert gases can derive CO by the Fick principle. ⋯ Mean peak VO2 was 12.6 +/- 4.7 ml/kg/min. A significant linear correlation was observed between peak VO2 and peak CO (r = 0.64, p <0.0001). In conclusion, combined metabolic stress testing with inert gas rebreathing can be easily performed in patients with HF.
-
In view of the importance of pulmonary embolectomy as a possible treatment option in highly compromised patients with acute pulmonary embolism, a systematic review of immediate surgical outcomes was performed. Pooled data from 46 reported case series of patients operated from 1961 to 2006 showed an average mortality of 389 of 1,300 patients (30%). ⋯ In patients who experienced cardiac arrest before pulmonary embolectomy, the operative mortality was 59% compared with 29% in patients who did not have preoperative cardiac arrest. In conclusion, despite generally high mortality in patients who undergo pulmonary embolectomy, it may have life-saving potential in some instances.