Fady F. Haddad

Low-Density Lipoprotein Levels and Not Mutation Status Predict Intima-Media Thickness in Familial Hypercholesterolemia

BACKGROUND Intima-media thickness (IMT) is a well-described marker of cardiovascular disease. In this study we aim to determine whether low-density lipoprotein (LDL) levels and disease-related mutation status can predict IMT in patients with severe familial hypercholesterolemia (FH) referred for or on LDL apheresis. METHODS Genetic screening, lipid profile testing, and IMT measurements were performed on a series of 33 severe FH patients (19 homozygous) on LDL apheresis treatments (LDL 447 ± 151 mg/dL, age range 6-60 years). Data were then compared with literature IMT-LDL data for normal subjects, mild FH patients, and severe FH patients (18, 41, and 6 studies, respectively). RESULTS Age-adjusted IMT was linearly related to LDL levels over a wide range of values (<500 mg/dL), except for the severe FH no-apheresis cohort. Alternatively, our severe FH population (mostly on apheresis) did follow the mild FH/control age-adjusted IMT-LDL relation. CONCLUSIONS In severe FH, measuring LDL levels is more predictive of increased IMT than genetic screening.

High-output cardiac failure secondary to a large arteriovenous fistula: a persistent threat to the dialysis and kidney transplant patient.

High-output cardiac failure secondary to a surgically constructed arteriovenous fistula (AVF) is a rare entity that is usually under-diagnosed in the dialysis population. We herein present a case of a 35-year-old female who was diagnosed with high-output cardiac failure secondary to an AVF and later managed with surgical division of the fistula. Risk factors associated with this entity are discussed, and preventive screening strategies are recommended.

Tunneled dialysis catheter tip migration in obese and large-breasted individuals

A 65-year-old obese woman with chronic kidney disease presented with acute deterioration requiring hemodialysis. A right internal jugular tunneled hemodialysis catheter was placed, with a chest X-ray (CXR) confirming tip position at the right atrium. On day 10 post-insertion, she was referred from her dialysis center because of bleeding from the tunnel and catheter exit site. Inspection of the catheter failed to show any evidence of displacement and the fixation sutures were intact. CXR showed cephalad migration of the catheter tip (Figure 1). A new tunneled catheter was inserted into the right internal jugular vein, this time using a medial parasternal tunnel (Figure 2).

Premature Valvular Heart Disease in Homozygous Familial Hypercholesterolemia

Valvular heart disease frequently occurs as a consequence of premature atherosclerosis in individuals with familial hypercholesterolemia (FH). Studies have primarily focused on aortic valve calcification in heterozygous FH, but there is paucity of data on the incidence of valvular disease in homozygous FH. We performed echocardiographic studies in 33 relatively young patients (mean age: 26 years) with homozygous FH (mean LDL of 447 mg/dL, 73% on LDL apheresis) to look for subclinical valvulopathy. Twenty-one patients had evidence of valvulopathy of the aortic or mitral valves, while seven subjects showed notable mitral regurgitation. Older patients were more likely to have aortic valve calcification (>21 versus ≤21 years: 59% versus 12.5%; p = 0.01) despite lower LDL levels at the time of the study (385 versus 513 mg/dL; p = 0.016). Patients with valvulopathy were older and had comparable LDL levels and a lower carotid intima-media thickness. Our data suggests that, in homozygous FH patients, valvulopathy (1) is present across a wide age spectrum and LDL levels and (2) is less likely to be influenced by lipid-lowering treatment. Echocardiographic studies that focused on aortic root thickening and stenosis and regurgitation are thus likely an effective modality for serial follow-up of subclinical valvular heart disease.

First Use of a Drug-Eluting Balloon in the Treatment of Acute Renal Artery Occlusion and In-stent Restenosis

In-stent restenosis in a renal artery (RA) of a solitary functioning kidney is a serious complication of RA stenting. Drug-eluting balloons (DEB) have emerged as a novel way to manage restenosis. In this paper, the authors reported the first use of a DEB in the treatment of severe in-stent restenosis and thrombosis of a drug-eluting stent deployed in a RA. The patient presented with oligo-anuria and a serum creatinine (Scr) of 9 mg/dL that improved back to baseline of 2 mg/dL after the successful procedure. The optimal use of DEB in similar cases will have to be determined by larger clinical trials.

Upper Extremity Fasciotomy

Compartment syndrome results from the combination of increased interstitial tissue pressure and the noncompliant nature of the fascia and osseous structures that make up a fascial compartment, causing microvascular compromise and subsequent muscle and nerve ischemia. Nerve conduction can be negatively affected after 2 h of ischemia; however, if compartment syndrome is diagnosed and treated within 6 h of onset, overall functional impairment is unlikely. Diagnosis of compartment syndrome can be made by clinical examination or with more objective measurements such as compartment pressures.

Endovascular Abdominal Aortic Aneurysm Repair with the Cook Zenith or Zenith Flex Endograft

Infrarenal abdominal aortic aneurysm (AAA) >5.5 cm (nonruptured) in men 5.0 cm in women, enlarging AAA >4.0 cm (grown >5 mm in 6 months), Common Iliac artery Aneurysm. Anatomic exclusions: Neck: Infrarenal neck length 32 or 60° relative to aneurysm long axis. Neck angulation >45° relative to suprarenal aorta. Inverted funnel. Circumferential thrombus. Iliacs: Iliac fixation site >10 mm in length and <20 mm in diameter.

Bypass Stenosis Angioplasty

1. If target lesion or plan is unclear from the preoperative duplex, we favor prepping and draping the patient from the start umbilicus to toes bilaterally in preparation for potential cut-down or open repair. 2. Get access from the contralateral leg if possible (refer to alternative below). 3. Advance angiographic catheter into aorta and perform aorto iliac and bilateral femoral imaging. 4. Manipulate catheter and wire to get cross-over access to the contralateral iliac.