The role of tyrosine kinase inhibitor "Lapatinib" in pulmonary hypertension.

INTRODUCTION: Pulmonary Arterial Hypertension (PAH) and cancer share growth factor and protein kinase signaling pathways that result in smooth muscle cell proliferation and vasculopathy. There is little known about the impact of Lapatinib on the pulmonary vasculature. After reporting a case of Lapatinib-induced PAH we investigated the association of Lapatinib with the development of PAH in our institution. METHODS: We reviewed charts for all patients treated with Lapatinib at our institution between 2008 and 2013. Patients who had undergone 2D-echocardiogram both prior to and after treatment were included in the analysis. Increase in Pulmonary artery systolic pressure (PASP) was assessed. Patients were also evaluated in terms of risk factors for non-Group 1 PAH. RESULTS: A total of 27 patients were found to have 2-D echo done before and after starting treatment with Lapatinib. Six patients were found to have significant increase in their PASP after starting treatment. Right heart catheterization before and after stopping the medication was available in three patient, confirming the diagnosis of PAH with complete resolution after stopping the medication. The median pre-treatment and post treatment PASP in those 6 patients was 29 mmHg and 65.5 mmHg respectively (N = 6; p = 0.027). CONCLUSION: Lapatinib might be associated with the development of PAH. PASP should be evaluated in patients who become short of breath while on treatment, and stopping the drug in cases where no other reasons are identified could be associated with reversibility of the elevated pulmonary artery pressure.

Drug coated balloon angioplasty for subclavian artery stenosis: A potential novel indication.

Subclavian artery stenosis is associated with increased cardiovascular disease mortality. It remains an important treatable cause of upper extremity, brain and cardiac ischemia. Endovascular treatment with angioplasty and stenting has become the preferred modality of treatment. Surgical revascularization is reserved for difficult cases with unfavorable anatomy to endovascular approach. Here we describe a case of subclavian artery stenosis causing subclavian steal syndrome with unfavorable anatomy to stenting treated successfully with drug coated balloon angioplasty with maintenance of patency at 6months.

Multiple and recurrent coronary stent fractures.

Coronary stent fracture is an increasingly recognized complication mainly involving drug-eluting stents. Important clinical implications, including in-stent restenosis and stent thrombosis, have been associated with this phenomenon. Variable incidence rates and several predisposing factors have been reported, but no general agreement exists on the best treatment strategy. We report a case of recurrent multiple left anterior descending artery sirolimus-eluting stent fractures, with variable clinical presentations ranging from recurrent angina to acute myocardial infarction and ventricular fibrillation cardiac arrest, that were ultimately treated with coronary artery bypass surgery.

Interplay of parathyroid hormone and aldosterone antagonist in prevention of heart failure hospitalizations in chronic kidney disease.

BACKGROUND: Aldosterone antagonists may mediate their effects on heart failure through parathyroid hormone (PTH) in chronic kidney disease (CKD) patients. METHODS: Patients with CKD on spironolactone were selected and matched for age, gender, race, use of a vitamin D analogue, the number of antihypertensive medications, and CKD stage. PTH levels before and after the first prescription of spironolactone were measured. A thorough chart review was conducted to assess for heart failure hospitalizations. An adjusted Cox proportional model was used to calculate the hazard ratio (HR) for heart failure hospitalizations among cases versus controls. RESULTS: There were a total of 950 (mean age 67±13 years, 40% men) patients with CKD. Of these, there were 48 hospitalizations for heart failure among the cases and 82 among the controls (HR 0.37; 95% confidence interval (CI) 0.19-0.74, p=0.005). We noted a more significant decrease in PTH levels among the cases when compared to the controls (p<0.0001). The adjusted hazard for heart failure hospitalization increased with higher PTH levels (p=0.002) and mediation analysis revealed change in PTH level as a significant mediator of heart failure hospitalization (p=0.04). CONCLUSION: Aldosterone antagonists may be helpful in preventing hospitalizations for heart failure exacerbation in CKD patients through a PTH-mediated effect.