Suhail Allaqaband

Prospective randomized study of N-acetylcysteine, fenoldopam, and saline for prevention of radiocontrast-induced nephropathy

The objective of this study was to compare the efficacy of N‐acetylcysteine (NAC), fenoldopam, and saline in preventing radiocontrast‐induced nephropathy (RCIN) in high‐risk patients undergoing cardiovascular procedures. We prospectively enrolled 123 patients who were scheduled for cardiovascular procedures and had a baseline creatinine > 1.6 mg/dl or creatinine clearance of < 60 ml/min. Patients were randomly assigned to receive either saline (0.45% normal saline at 1 cc/kg) for 12 hr before and 12 hr after the procedure, or fenoldopam (0.1 μg/kg/min) plus saline for 4 hr prior and 4 hr after the procedure, or NAC orally (600 mg) plus saline every 12 hr for 24 hr prior and 24 hr after the procedure. All the patients received low‐osmolality nonionic contrast. RCIN was defined as an increase in creatinine level > 0.5 mg/dl after 48 hr. The incidence of RCIN was 17.7% in the NAC group, 15.3% in the saline group, and 15.7% in the fenoldopam group (P = 0.919). Of the 20 patients who developed RCIN, 2 required dialysis. Serum creatinine decreased after 48 hr (vs. baseline) in 38% patients in the NAC group, 18% in the fenoldopam group, and 15% in the saline group. In patients with chronic renal insufficiency, NAC or fenoldopam offered no additional benefit over hydration with saline in preventing RCIN. Cathet Cardiovasc Intervent 2002;57:279–283.

Stent fracture, an incidental finding or a significant marker of clinical in-stent restenosis?

The predictors and clinical significance for stent fracture (SF) in drug‐eluting stents (DES) remain unknown. We identified procedural factors leading to SF and its clinical consequences in DES.

“The chimney graft”—A simple technique for endovascular repair of complex juxtarenal abdominal aortic aneurysms in no‐option patients

Endovascular aneurysm repair (EVAR) has developed as a less invasive alternative to open surgery for patients with abdominal aortic aneurysms. However, patients with very short infrarenal necks require complex surgical open repair, which is associated with increased mortality and morbidity. The risk of complex open repair may be prohibitive in high‐risk patients. Thus, modifying the technique of EVAR may be required in such patients to successfully exclude aneurysms. An alternative that can be used in these patients is the so‐called “chimney graft” technique. We report two cases where the chimney graft technique was used with good immediate results.

Endovascular intervention of aortoiliac occlusive disease in high‐risk patients using the kissing stents technique: Long‐term results

Endovascular intervention deploying a kissing stents (KS) technique has been used as an alternative to surgical intervention in treating symptomatic aortoiliac occlusive disease. However, the long‐term results on high‐risk patients are unknown. We retrospectively analyzed data on high‐risk patients who underwent endovascular intervention using the KS technique at our institution. Fifty high‐risk patients aged 62 ± 6.4 years with severe aortoiliac stenosis underwent stent‐supported angioplasty using the KS technique. Thirty percent of the patients had total occlusion of the distal aorta and/or the iliac arteries. Twelve patients received thrombolytics prior to stenting. The procedure was successful in all 50 patients. There was a 4% acute complication rate (distal embolization). However, there were no vascular complications, myocardial infarction, or perioperative death. Primary patency during follow‐up of 20 ± 12.3 months was 92%, while secondary patency rate was 100%. Amputation‐free survival was 100%. Ninety‐two percent remained free of lifestyle‐limiting claudication.Catheter Cardiovasc Interv 2003;60:320–326.© 2003 Wiley‐Liss, Inc.

A case of popliteal stent fracture with pseudoaneurysm formation.

We describe a case of angiographically documented stent fracture and pseudoaneurysm formation in a patient with femoropopliteal disease, which was successfully treated with deployment of an endovascular stent graft. Technical aspects of the procedure are discussed and the experience with stent fractures previously reported in the literature is reviewed.

Endovascular treatment of peripheral vascular disease.

Peripheral arterial disease (PAD) affects about 27 million people in North America and Europe, accounting for up to 413,000 hospitalizations per year with 88,000 hospitalizations involving the lower extremities and 28,000 involving embolectomy or thrombectomy of lower limb arteries. Many patients are asymptomatic and, among symptomatic patients, atypical symptoms are more common than classic claudication. Peripheral arterial disease also correlates strongly with risk of major cardiovascular events, and patients with PAD have a high prevalence of coexistent coronary and cerebrovascular disease. Because the prevalence of PAD increases progressively with age, PAD is a growing clinical problem due to the increasingly aged population in the United States and other developed countries. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, endovascular practice, percutaneous transluminal angioplasty with or without stenting, is used far more frequently for all types of lower extremity occlusive lesions, reflecting the continuing advances in imaging techniques, angioplasty equipment, and endovascular expertise. The role of endovascular intervention in the treatment of limb-threatening ischemia is also expanding, and its promise of limb salvage and symptom relief with reduced morbidity and mortality makes percutaneous transluminal angioplasty/stenting an attractive alternative to surgery and, as most endovascular interventions are performed on an outpatient basis, hospital costs are cut considerably. In this monograph we discuss current endovascular intervention for treatment of occlusive PAD, aneurysmal arterial disease, and venous occlusive disease.

Combined use of Impella device and intra-aortic balloon pump to improve survival in a patient in profound cardiogenic shock post cardiac arrest.

Patients who suffer cardiogenic shock after cardiac arrest have a very poor prognosis. Left ventricular assist devices have proven to be useful in these patients to improve survival. Recently introduced percutaneous assist devices are easier to use and can be inserted quickly in the catheterization laboratory. We describe a case where intra‐aortic balloon pump by itself was not enough to provide hemodynamic support in a patient with cardiogenic shock after cardiac arrest. The Impella Recover® LP 2.5 system (ABIOMED, Inc., Danvers, MA) was successfully used along with the balloon pump for hemodynamic support and resulted in dramatic improvement of the patients condition.

Prevention of contrast-induced acute kidney injury in patients with stable chronic renal disease undergoing elective percutaneous coronary and peripheral interventions: Randomized comparison of two preventive strategies†

Objective: We compared use of intravenous (IV) normal saline (NS) to sodium bicarbonate (NaHCO3) with or without oral N‐acetylcysteine (NAC) for prevention of contrast‐induced acute kidney injury (CI‐AKI). Background: CI‐AKI is associated with significant adverse clinical events. Use of NAC has produced variable results. Recently, intravenous hydration with NaHCO3 for CI‐AKI prophylaxis has been adopted as standard treatment for patients with stable chronic renal disease undergoing catheterization procedures. Methods: We prospectively enrolled 320 patients with baseline renal insufficiency scheduled to undergo catheterization. Patients were randomly assigned to receive either IV NS ± NAC (n = 161) or IV dextrose 5% in water containing 154 mEq/l of NaHCO3 ± NAC (n = 159). IV NS was administered at 1 ml/kg body weight for 12 hr preprocedure and 12 more hr postprocedure. IV NaHCO3 was administered at 3 ml/kg body weight for 1 hr preprocedure followed by 1 ml/kg body weight postprocedure. A 1,200 mg oral dose of NAC was given 2–12 hr preprocedure and 6–12 hr postprocedure in 50% of patients in each study arm. CI‐AKI was defined as an increase of >0.5 mg/dl or >25% above baseline creatinine. Results: Overall incidence of CI‐AKI was 10.3%. There was no significant difference in incidence among the two groups (NS ± NAC 11.8% vs. NaHCO3 ± NAC 8.8%, p = ns). Incidence of CI‐AKI increased with increasing age (p = 0.001), contrast agent use >3 ml/kg body weight (p = 0.038) and diuretic use (p = 0.005). Conclusion: Incidence of CI‐AKI was no different in the NaHCO3 group compared to NS group, and NAC did not reduce CI‐AKI in the two study arms.

Identifying False-positive ST-elevation Myocardial Infarction in Emergency Department Patients

BACKGROUND In a push to treat ST-elevation myocardial infarction (STEMI) patients with primary percutaneous coronary intervention (PCI) within 90 min of door-to-balloon time, emergency cardiac catheterization laboratory activation protocols bypass routine clinical assessments, raising the possibility of more frequent catheterizations in patients with no culprit coronary lesion. OBJECTIVE To determine the incidence, predictors, and prognosis of false-positive STEMI. METHODS We followed a prospective cohort of patients diagnosed with STEMI by usual criteria receiving emergency cardiac catheterization with intention of primary PCI between January 2005 and December 2007 at a tertiary care center. False-positive STEMI was defined as absence of a clear culprit lesion on coronary angiography. RESULTS Of 489 patients who received emergency cardiac catheterization indicated for STEMI, 54 (11.0%, 95% confidence interval [CI] 8.3-13.8) had no culprit lesion on coronary angiography. Independent predictors of false-positive STEMI were absence of chest pain (odds ratio [OR] 18.2, 95% CI 3.7-90.1), no reciprocal ST-segment changes (OR 11.8, 95% CI 5.14-27.3), fewer than three cardiovascular risk factors (OR 9.79, 95% CI 4.0-23.8), and symptom duration longer than 6h (OR 9.2, 95% CI 3.6-23.7); all p<0.001. Using predictors, we modeled a risk score that achieved 88% (95% CI 81-94%) accuracy in identifying patients with negative coronary angiography. Among the false-positive STEMI patients, 48.1% had other serious diagnoses related to their electrocardiographic findings. CONCLUSION When the diagnosis of STEMI is in doubt, clinicians may use predictors to quickly reassess the likelihood of an alternative diagnosis.

Access Site Complications After Peripheral Vascular Interventions Incidence, Predictors, and Outcomes

Background—Access site hematomas and pseudoaneurysms are the most frequent complications of peripheral vascular intervention (PVI); however, their incidence and risk factors remain unclear. Methods and Results—We retrospectively analyzed data from the multicenter Vascular Quality Initiative on 22 226 patients who underwent 27 048 PVI from August 2007 to May 2013. Primary end points included incidence and predictors of access site complications (ASCs), length of postprocedural hospitalization, discharge status, and 30-day and 1-year mortality. ASC complicated 936 procedures (3.5%). Of these, 74.4% were minor complications, 9.7% were moderate requiring transfusion, 5.4% were moderate requiring thrombin injection, and 10.5% were severe requiring surgery. Predictors of ASC were age >75 years, female sex, white race, no prior PVI, nonfemoral arterial access site, >6-Fr sheath size, thrombolytics, arterial dissection, fluoroscopy time >30 minutes, nonuse of vascular closure device, bedridden preoperative ambulatory status, and urgent indication. Mean hospitalization was longer after procedures complicated by ASC (1.2±1.6 versus 1.9±1.9 days; range, 0–7 days; P=0.002). Severity of ASC correlated with higher rates of discharge to rehabilitation/nursing facilities compared with home discharge. Patients with severe ASC had higher 30-day mortality (6.1% versus 1.4%; P<0.001), and those with moderate ASC requiring transfusion had elevated 1-year mortality (12.1% versus 5.7%; P<0.001). Conclusions—Several factors independently predict ASC after PVI. Appropriate use of antithrombotic therapies and vascular closure device in patients at increased risk of ASC may improve post-PVI outcomes.