Satjit Adlakha

Renal Ischemia Regulates Marinobufagenin Release in Humans

Cardiotonic steroids, including marinobufagenin, are a group of new steroid hormones found in plasma and urine of patients with congestive heart failure, myocardial infarction, and chronic renal failure. In animal studies, partial nephrectomy induces marinobufagenin elevation, cardiac hypertrophy, and fibrosis. The objective of this study is to test the effect of renal ischemia on marinobufagenin levels in humans with renal artery stenosis (RAS). To test this, plasma marinobufagenin levels were measured in patients with RAS of the Prospective Randomized Study Comparing Renal Artery Stenting With or Without Distal Protection, non-RAS patient controls who were scheduled for coronary angiography, and normal healthy individuals. Marinobufagenin levels were significantly higher in patients with RAS compared with those of the other 2 groups. Multivariate analysis shows that occurrence of RAS is independently related to marinobufagenin levels. In addition, renal artery revascularization by stenting partially reversed marinobufagenin levels in the patients with RAS (0.77±0.06 nmol/L at baseline; 0.66±0.06 nmol/L at 24 hours; and 0.61±0.05 nmol/L at 1 month). In conclusion, we have found that marinobufagenin levels are increased in patients with RAS, whereas reversal of renal ischemia by stenting treatment reduces marinobufagenin levels. These results suggest that RAS-induced renal ischemia may be a major cause of marinobufagenin release.

Endovascular therapy for radiation-induced pulmonary artery stenosis: A case report and review of the literature

Although pulmonary artery stenosis and its treatment has been well characterized in pediatric populations, its diagnosis and even how to determine the significance of a stenosis can be difficult and optimal management is currently unknown. This case report and review of the literature outlines how we successfully diagnosed, evaluated, and stented a patient with radiation induced pulmonary artery stenosis. This case further adds support to a very limited data pool suggesting that percutaneous angioplasty of pulmonary artery stenosis may be a safe and effective treatment option for this unique patient population.

Platelet Activation in Patients with Atherosclerotic Renal Artery Stenosis Undergoing Stent Revascularization

BACKGROUND AND OBJECTIVES Soluble CD40 ligand (sCD40L) is a marker of platelet activation; whether platelet activation occurs in the setting of renal artery stenosis and stenting is unknown. Additionally, the effect of embolic protection devices and glycoprotein IIb/IIIa inhibitors on platelet activation during renal artery intervention is unknown. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Plasma levels of sCD40L were measured in healthy controls, patients with atherosclerosis without renal stenosis, and patients with renal artery stenosis before, immediately after, and 24 hours after renal artery stenting. RESULTS Soluble CD40L levels were higher in renal artery stenosis patients than normal controls (347.5 ± 27.0 versus 65.2 ± 1.4 pg/ml, P < 0.001), but were similar to patients with atherosclerosis without renal artery stenosis. Platelet-rich emboli were captured in 26% (9 of 35) of embolic protection device patients, and in these patients sCD40L was elevated before the procedure. Embolic protection device use was associated with a nonsignificant increase in sCD40L, whereas sCD40L declined with abciximab after the procedure (324.9 ± 42.5 versus 188.7 ± 31.0 pg/ml, P = 0.003) and at 24 hours. CONCLUSIONS Atherosclerotic renal artery stenosis is associated with platelet activation, but this appears to be related to atherosclerosis, not renal artery stenosis specifically. Embolization of platelet-rich thrombi is common in renal artery stenting and is inhibited with abciximab.

Coronary stent fracture: a cause of cardiac chest pain?

Inherent risks of coronary artery stenting include restenosis and thrombosis. More recently, stent fractures (SF) have emerged as a complication. Lengthy coronary stents, overlapping stents, saphaneous vein graft stents, and right coronary artery lesions treated with sirolimus-eluting stents (SES; Cypher, Cordis, Miami Lakes, Florida, USA) are some of the predisposing factors that have been linked to fractures. Early detection and management may help alleviate the complications of SF including acute thrombosis and restenosis at the site of fracture. We present an interesting case of a SES fracture in the left main coronary artery.

Live 3D TEE demonstrates and guides the management of prosthetic mitral valve obstruction.

A 43‐year‐old woman, with a remote history of rheumatic mitral stenosis and a St. Jude prosthetic mitral valve replacement, presented with shortness of breath and palpitations, shortly after a long flight. On admission, atrial fibrillation with a rapid ventricular response was noted in the setting of a long history of noncompliance with her anticoagulation. Transesophageal echocardiography (TEE) demonstrated multiple laminated thrombi in the left atrial appendage. Live three‐dimensional (3D) TEE confirmed this diagnosis and demonstrated an immobile posterior leaflet of the mitral prosthesis, which had direct implications in her management. She successfully underwent surgery for mitral valve replacement, left atrial appendage ligation, and a Maze procedure on the following day. The multiple thrombi within the atrial appendage were confirmed intraoperatively and pannus formation was determined to be the etiology of the leaflet immobility. (Echocardiography 2011;28:E146‐E148)

Percutaneous intervention for chronic total occlusion of the internal iliac artery for unrelenting buttock claudication.

Internal iliac artery stenosis or occlusion has been documented to cause hip pain, erectile dysfunction, and buttock claudication. Endovascular repair for patients with significant stenosis has been well documented, but chronic total occlusion revascularizations have not been reported in the literature. The reluctance to attempt percutaneous intervention may be in part due to the extensive collateralization that forms to this vessel, or fear of complications such as wire perforation in a vessel that has a tortuous route with multiple bifurcations. This report describes two cases of patients with unrelenting buttock claudication that completely resolved after percutaneous intervention of unilateral chronic total occlusions of the internal iliac artery.