Israel Medical Association Journal

Background: Renal artery stenosis is one of the most frequent causes of secondary hypertension. Appropriate methods for screening, diagnosis and therapy are currently under debate.

Objectives: To evaluate and recommend methods for screening and diagnosing renal artery stenosis, and to assess the clinical outcomes of renal artery stenting.

Methods: A total of 450 patients undergoing non-emergent coronary angiography fulfilled the selection criteria for selective renal arteriography; those with severe (luminal narrowing ≥ 70%) renal artery stenosis underwent percutaneous transluminal renal angioplasty with renal artery stenting.

Results: Of 166 patients (36.9%) with renal artery stenosis, 41 (9.1%) had severe stenosis that required renal artery stenting, and 83% had ostial renal stenosis. The primary success rate was 100% and there were no complications. During the follow-up period, two patients required a second PTRA[1]. After stent deployment, significant reductions were observed in systolic and diastolic pressures (P < 0.001 and P = 0.01, respectively) and in the number of antihypertensive drugs used by the patients (P < 0.001). These reductions were sustained during follow-up. Hypertension was cured (systolic blood pressure < 130 mmHg) in 9 (21.4%) and improved in 27 (64.3%) patients. Plasma creatinine did not change significantly.

Conclusions: Selective renal angiography is an effective diagnostic tool for identifying symptomatic cases of renal artery stenosis in patients undergoing coronary angiography. Our finding of a high success rate and low complication rate supports the use of primary renal artery stenting in symptomatic patients with renal artery stenosis.

Background: Tubeless percutaneous nephrolithotomy is defined as PCNL[1] without postoperative nephrostomy tubes. It is reported to reduce postoperative pain, hospital stay and recovery time. To date the procedure has been reserved for selected patients.

Objectives: To assess our initial experience in extending the implementation of tubeless PCNL without preoperative patient selection.

Methods: All consecutive PCNLs performed during 2004–2008 were evaluated. Tubeless PCNL was performed when residual stones, bleeding and extravasation were excluded intraoperatively. Staghorn stones, stone burden, supracostal and multiple accesses, anatomic anomalies, solitary kidneys and operative time were not considered contraindications. We analyzed the clinical data and the choice of tubeless PCNL over time.

Results: Of 281 PCNLs performed during the study period, 200 (71%) were tubeless. The patients' average age was 53 years (range 28–82 years), the stone burden was 924 mm² (400–3150 mm²), operative time was 99 minutes (45–210 min), complication rate was 14% and immediate stone-free rate 91%. There were 81 conversions to standard PCNL (29%) due to expected second-look (n=47, 58%), impression of bleeding (n=21, 26%), suspected hydrothorax (n=7, 9%) and extravasation (n=6, 7%). The transfusion rate was 1%. The median hospital stay was 1 day (1–15 days) and recovery time 7 days (5–20 days). The rate of implementing the tubeless procedure increased steadily along time from 46% to 83% (P = 0.0001). 

Conclusions: Tubeless PCNL can be safely and effectively performed based on intraoperative decisions, without preoperative contraindications. They are easily accommodated by experienced endourologists and provide real advantages.

Background: Critical limb ischemia is an increasingly common condition that has high surgical morbidity and limited non-surgical options.  

Objectives: To evaluate the use of silicon carbide-coated Motion stents, as compared to reported data for bare metal stents, in elderly patients with infrapopliteal artery stenoses causing critical limb ischemia after failed or complicated percutaneous transluminal angioplasty.

Methods: Between January 2003 and March 2004, 41 stents were inserted into 17 consecutive patients (11 males, 6 females, mean age 82 years, range 75–93) following unsuccessful or complicated PTA[1]. Seven patients had one-vessel run-off, six had two-vessel and four had three vessel run-off. All patients suffered from CLI[2], had up to three lesions and more than one co-morbid condition, and were considered at high surgical risk. Silicon carbide-coated Motion coronary stents, 2.5–4 mm diameter and 25 and 30 mm length, were used. Pre-intervention assessment included clinical condition, ankle brachial index, Doppler ultrasound and digital subtracted angiography. Post-intervention evaluation included clinical condition, ABI[3], and Doppler ultrasound at 3, 6 and 12 months.

Results: The technical success rate per lesion was 100% (41/41). Two patients died of unrelated causes after 2 and 8 months respectively. Primary patency rates with duplex ultrasound were 68.7% (11/16) at 3 months, 43.7% (7/16) at 6 months and 40% (6/15) after 12 months. Nine patients developed complete occlusion in 13 stents; three of these patients underwent a below-knee amputation and two patients a partial foot amputation. Re-intervention (PTA only) was performed in 7 patients (43.7%). Secondary patency rate was 81.2% (13/16) at 6 months and 60% (9/15) at one year. Mean ABI index had improved at 6 months from 0.32 to 0.67, and to 0.53 at one year. Clinical improvement was evident in 87.5% (14/16) at 6 months and in 66.6% (10/15) at one year.

Conclusions: Silicon carbide-coated stents are comparable to bare metal stents after 6 and 12 months in infrapopliteal interventions in CLI when stenting is indicated.

Background: Stent thrombosis is a rare but devastating complication of coronary stent implantation. The incidence and potential predictors were assessed in a "real world” single center.

 Objectives: To examine whether socioeconomic status indeed affects the occurrence of stent thrombosis.

Methods: We searched our database for cases of "definite" stent thrombosis (according to the ARC Dublin definitions). Each case was matched by procedure date, age and gender; three cases of stenting did not result in stent thrombosis. Demographic and clinical parameters were compared and socioeconomic status was determined according to a standardized polling and market survey database.

Results: A total of 3401 patients underwent stent implantation in our hospital during the period 2004–2006. Their mean age was 63 ± 11 years, and 80% were males. Twenty-nine cases (0.85%) of “definite” sub-acute/late stent thrombosis were recorded. Mortality at 30 days was recorded in 1 patient (3.5%). Thrombosis occurred 2 days to 3 years after stent implantation. All patients presented with acute myocardial infarction. Premature clopidogrel discontinuation was reported in 60%. Patients with stent thrombosis had significantly higher rates of AMI[1] at the time of the initial procedure (76 vs. 32%, P < 0.001) and were cigarette smokers (60 vs. 28%, P < 0.001). Drug-eluting stents were used less in the stent thrombosis group. There was no difference in stent diameter or length between the two groups. Socioeconomic status was significantly lower at the stent thrombosis group, 3.4 ± 2.4 vs. 5.4 ± 2.6 (mean ± SD, scale 1–10, P < 0.01).

Conclusions: The incidence rate of stent thrombosis is at least 0.85% in our population. It appears in patients with significantly lower socioeconomic status and with certain clinical predictors. These results warrant stricter follow-up and support the policy of healthcare providers regarding patients at risk for stent thrombosis.

Background: Although unprotected left main coronary artery disease is considered by contemporary guidelines to be an indication for surgery, percutaneous coronary intervention may be necessary in patients at high surgical risk.

Objectives: To assess the outcome of angioplasty in the treatment of unprotected LMCA[1] disease.

Methods: Angiographic and clinical data were collected prospectively for all patients who underwent emergent or non-emergent (planned) therapeutic PCI[2] for unprotected LMCA disease at our center from 2003 to 2007. Baseline values were compared with findings at 1, 6 and 12 months after the procedure.

Results: The study group comprised 71 consecutive patients with a mean age of 74 ± 12 years; 63% were men, and 31% had diabetes. Forty-three patients had a planned procedure and 28 an emergent procedure. Mean EuroScore was 7.3 ± 3.6 (range 5–12). Forty-nine percent of the procedures were performed with bare metal stents and 51% with drug-eluting stents. Procedural success was achieved in 100% of cases. The overall mortality rate was 11.3% at 1 month, 18.3% at 6 months and 19.7% at 12 months. Elective PCI was associated with significantly lower mortality (2.3% vs. 25% at 1 month, 4.6% vs. 39% at 6 months and 6.9% vs. 39% at 12 months), and the use of drug-eluting stents was associated with lower rates of target vessel revascularization and major adverse cardiac events than use of bare metal stents (2.8% vs. 14% at 1 month, 8.3% vs. 43% at 6 and 12 months). Variables that correlated with increased mortality or MACE[3] at 6 and 12 months were cardiogenic shock, emergent PCI, ejection fraction < 35%, renal failure, distal left main stenosis location, and reference diameter < 3 mm.

Conclusions: PCI is a feasible and relatively safe therapeutic option for unprotected LMCA. The less favorable outcome of emergent compared to planned PCI is probably attributable to the overwhelming acute myocardial ischemic injury in emergent cases. The use of drug-eluting stents may improve the intermediate-term restenosis rate.

[1] LMCA = left main coronary artery

[2] PCI = percutaneous coronary intervention

The histopathology of severe persistent asthma and chronic obstructive pulmonary disease is predominantly characterized by neutrophilic inflammation. It is posited that chronic hypoxia from hypoventilation in combination with hypoperfusion and hypercapnia are associated with induction of pulmonary tissue acidosis in SPA[1] and COPD[2], which in turn provide ideal conditions to induce danger-associated molecular patterns, i.e., crystallized and calcium pyrophosphate. These stimuli in combination with other danger-related biochemical signals are capable of stimulating an innate immune receptor (cryopyrin inflammasome, NALP3) and cause interleukin-1β secretion with subsequent neutrophilic inflammation. There is evidence to suggest that the mechanisms and pathobiology associated with chronic hypoxia, reduced perfusion and reoxygenation in SPA/COPD may exhibit similarities to the biphasic pathobiology involved in ischemia-reperfusion injury. A rationale is suggested for trials of IL-1β[3] targeted therapies as an adjunct strategy to control neutrophilic inflammation in these conditions.

Background: Carotid artery stenting is used as an alternative to surgical endarterectomy.

Objectives: To determine the outcome of CAS[1] in a retrospective cohort of patients.

Methods: Between July 1999 and March 2003, 56 consecutive patients with carotid artery stenosis who were considered ineligible for surgery were treated (45 male, 11 female, mean age 69). All cases were performed prior to the introduction of distal protective devices in Israel.

Results: Intraprocedural complications included transient neurological findings in 5 patients (8%), cerebrovascular accident in 2 (3%), hemodynamic changes in 11 (18%), and 4 procedural failures. Post-procedural complications included transient ischemic attack in 3 patients and cardiovascular accident in 6 (10%). At 30 days follow-up, three patients (5%) remained with signs of CVA[2]. Two patients (3%) died during the post-procedural period and 16 (28%) during the 5 year follow-up, one due to recurrent CVA and the remainder to non-neurological causes. Five-year carotid Doppler follow-up was performed in 25 patients (45%), which revealed normal stent flow in 21 (84%), 50–60% restenosis in 3 patients (12%) and > 70% restenosis in one patient (4%).

Conclusions: This study confirms that stent procedures are beneficial for symptomatic carotid stenosis in patients not eligible for surgery.

Background: In recent years there has been an increase in endovascular repair of thoracic aortic aneurysms. In cases of insufficient neck length, occlusion of left subclavian artery achieves proper sealing and is usually well tolerated. Selected cases require revascularization of the left subclavian artery, including patients after coronary bypass surgery (left internal mammary to left anterior descending) and those with arm claudication or subclavian steal syndrome.

Objectives: To evaluate the tolerability of left subclavian artery occlusion by stent graft without revascularization.

Methods: Thirty patients with thoracic aortic aneurysms underwent endovascular repair between July 2000 and November 2004. Eleven of them had occlusion of the left subclavian artery that required revascularization in two. Follow-up (average 3 years) included a) blood pressure measurements of both arms at rest, after effort and pulse palpation, and b) vertebral blood flow by duplex scan.

Results: Of nine patients with no revascularization, 8 (89%) tolerated left subclavian artery occlusion with no claudication or steal syndrome; one (11%) suffered mild claudication only after effort and required no intervention. No left radial pulses were palpated in the nine patients. Blood pressure measurements in the left arm showed an average decrease of 40%, which remained constant after induced effort in all patients and was clinically insignificant. Duplex scan demonstrated reverse flow in the left vertebral artery in 8 of 9 patients (89%) and occlusion in 1 (originating in the arch and covered by the stent graft) with no clinical symptoms.

Conclusions: Left subclavian artery occlusion by stent graft is a tolerable procedure in the long term. In most cases, the constant decrease in blood pressure remained unchanged during follow-up and had no significant adverse affects. Most patients do not require revascularization prior to the endovascular procedure.
 

Background: Patients with severe persistent asthma despite GINA 2002 step 4 treatment are at risk for asthma-related morbidity and mortality. This study constitutes the Israeli arm of the international INNOVATE study.

Objectives: To determine the efficacy and safety of Xolair® as an add-on treatment in patients with severe persistent asthma.

Methods: Asthma patients (age 12–75 years) not controlled with high dose inhaled corticosteroids and long-active beta-2 agonists were randomized to receive either Xolair® or placebo for 28 weeks in a double-blind study in two Israeli centers.

Results: Thirty-three patients, 20 females and 13 males, mean age 54 ± 11.7 years, were included in the Israeli arm of the INNOVATE study. There were neither major adverse events nor withdrawals from the study. Xolair® (omalizumab) significantly reduced the rate of clinically significant asthma exacerbations (55% reduction) and all asthma-related emergency visits (53% reduction).
Conclusions: In patients with severe persistent difficult-to-treat asthma, despite regular treatment with LABA[1] and inhaled corticosteroids (GINA 2002 step 4), Xolair® is a safe and effective treatment

Background: Endobronchial stents are used to treat symptomatic patients with benign or malignant airway obstructions.

Objectives: To evaluate the safety and outcome of airway stent insertion for the treatment of malignant tracheobronchial narrowing.

Methods: The files of all patients with malignant disease who underwent airway stent insertion in our outpatient clinic from June 1995 to August 2004 were reviewed for background data, type of disease, symptoms, treatment, complications, and outcome.

Results: Airway stents were used in 34 patients, including 2 who required 2 stents at different locations, and one who required 2 adjacent stents (total, 37 stents). Ages ranged from 36 to 85 years (median 68). Primary lung cancer was noted in 35% of the patients and metastatic disease in 65%. Presenting signs and symptoms included dyspnea (82%), cough (11.7%), hemoptysis (9%), pneumonia (5.9%), and atelectasis (3%). The lesions were located in the left mainstem bronchus (31%), trachea (26%), right mainstem bronchus (26%), subglottis (14.3%), and bronchus intermedius (2.9%). Conscious sedation alone was utilized in 73% of the patients, allowing for early discharge. Eighteen patients (50%) received brachytherapy to the area of obstruction. Complications included stent migration (one patient) and severe or minimal bleeding (one patient each). Ninety-four percent of the patients reported significant relief of their dyspnea. Three of the four patients who had been mechanically ventilated before the procedure were weaned after stent insertion. Median survival from the time of stent placement was 6 months (range 0.25–105 months).

Conclusion: Stent placement can be safely performed in an outpatient setting with conscious sedation. It significantly relieves the patient's symptoms and may prolong survival.