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Aortic dissection is a rare but potentially fatal complication of percutaneous coronary intervention (PCI). Management strategies of PCI induced dissection are not clearly identified in literature; such occurrences often mandate surgical repair of the aortic root with reimplantation of the coronary arteries. Another trend seen in case reports is the use of coronary-aortic stenting if such lesions permit. Several factors impact the management decision including the hemodynamic stability of the patient; mechanism of aortic injury; size, severity, and direction of propagation of the dissection; presence of an intimal flap; and preexisting atherosclerotic disease. We describe a case of a 65-year-old woman who underwent PCI for a chronic right coronary artery (RCA) occlusion, which was complicated by aortic dissection and pericardial effusion. Our case report suggests that nonsurgical management may also be appropriate for PCI induced dissections, and potentially even those associated with new pericardial effusion.

Base Excision Repair (BER) is a major DNA repair pathway involved in the processing of exogenous nonbulky base damages from certain classes of cancer chemotherapy drugs as well as ionizing radiation. Methoxyamine (MX) is a small molecule chemical inhibitor of BER that is shown to enhance chemotherapy and/or ionizing radiation cytotoxicity in human cancers. In this paper, we have analysed the inhibitory effect of MX on the base excision repair pathway kinetics using a computational model of the repair pathway. The inhibitory effect of MX depends on the base excision repair efficiency. We have generated variable efficiency groups using different sets of protein concentrations generated by Latin hypercube sampling, and we have clustered simulation results into high, medium and low efficiency repair groups. From analysis of the inhibitory effect of MX on each of the three groups, it is found that the inhibition is most effective for high efficiency base excision repair, and least effective for low efficiency repair.

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Lower body positive pressure (LBPP) treadmill activity might benefit patients with heart failure (HF). To determine the short-term effects of LBPP on left ventricular (LV) function in HF patients, LV ejection duration (ED), a measure of systolic function was prospectively assessed in 30 men with stable HF with LV ejection fraction ≤ 40% and 50 healthy men (N). Baseline measurements (100% body weight), including blood pressure (BP), heart rate (HR) and LVED, obtained via radial artery applanation tonometry, were recorded after 2 minutes of standing on weight support treadmill and after LBPP achieving reductions of 25%, 50%, and 75% of body weight in random sequence. Baseline, HR, and LVED (251 ± 5 vs 264 ± 4 ms; P = .035) were lower in the HF group. The LBPP lowered HR more (14% vs 6%, P = .009) and increased LVED more (15% ± 7% vs 10% ± 6%; P = .004) in N versus HF. Neither group had changes (Δ) in BP. On generalized linear regression, the 2 groups showed different responses (P < .001). Multivariate analysis showed %ΔHR (P < .001) and HF (P = .026) were predictive of ΔED (r 2 = 0.44; P < .001). In conclusion, progressive LBPP increases LVED in a step-wise manner in N and HF patients independent of HR lowering. The ΔLVED is less marked in patients with HF.