Determinants and outcomes of asystole during carotid artery stenting.

PURPOSE: To examine the predictors and outcomes of asystole in patients who undergo carotid artery stenting (CAS). METHODS: Forty-three patients (24 men; median age 69 years) with asystole were identified after reviewing the case records of 884 patients who underwent CAS at our institution between 1997 and 2009. The control group comprised 678 patients who underwent stenting in the carotid sinus area without asystole. Univariate and multivariate logistic analyses were used to determine the predictors and outcomes of asystole. RESULTS: A right-sided procedure was more likely to result in asystole [odds ratio (OR) 11.4, 95% CI 4.0 to 32.7, p<0.0001] compared with a left-sided procedure. Patients with a contralateral carotid stenosis (OR 1.7, 95% CI 1.0 to 2.8, p = 0.04) and a left ventricular ejection fraction (LVEF) of <40% (OR 2.2, 95% CI 1.1 to 4.5, p = 0.03) were also more likely to suffer asystole. Smokers appeared less likely to develop asystole (OR 0.25, 95% CI 0.12 to 0.56, p = 0.0006). Periprocedural stroke (14% vs. 1.3%, p<0.001), length of stay during index hospitalization (2.2 vs. 1.2 days, p = 0.002), and 30-day mortality (11.6% vs. 4.1%, p = 0.02) were significantly higher in the asystole group. CONCLUSION: Asystole during CAS is more likely to occur in patients undergoing procedures in the right carotid sinus area, in those who have significant contralateral carotid stenosis, and in those with a reduced LVEF. More caution should be exercised during right-sided than left-sided CAS procedures.

Clinical features and usefulness of cardiac magnetic resonance imaging in assessing myocardial viability and prognosis in Takotsubo cardiomyopathy (transient left ventricular apical ballooning syndrome).

In Takotsubo cardiomyopathy, or transient left ventricular (LV) apical ballooning syndrome, normalization of wall motion can occur after as long as 3 months. We report 1 of the largest series to date outside Japan and emphasize the utility of cardiac magnetic resonance imaging (CMR) to show a lack of irreversible damage in the acute setting, thereby reliably predicting recovery. During the previous 6 years, we saw 22 patients who met the following criteria: (1) a suspected myocardial infarction based on symptoms, an abnormal electrocardiogram, and/or elevated serum cardiac markers; (2) an anteroapical wall motion abnormality; and (3) no significant occlusive epicardial coronary artery disease or observed vasospasm. Ten patients underwent delayed enhancement CMR to assess myocardial viability during the index presentation. All 10 patients had an absence of irreversible damage, as evidenced by lack of gadolinium "hyperenhancement"; later, their LV function returned to normal. Eight other patients, available for outpatient follow-up evaluation, also had normalization of LV function. Takotsubo cardiomyopathy is increasingly being recognized outside Japan and must be distinguished from acute myocardial infarction. In conclusion, CMR is useful to document segmental LV dysfunction and lack of irreversible damage and to predict functional recovery.

Cryoplasty for peripheral artery disease in an unselected patient population in a tertiary center.

Endovascular treatment of peripheral artery occlusive disease has suboptimal long-term patency rates. The addition of cryoplasty to balloon angioplasty, which involves the application of cold thermal energy to atherosclerotic plaque, might improve outcomes and decrease the need for reintervention. At a single tertiary center, we retrospectively analyzed data from the angiograms and medical records of unselected patients who underwent cryoplasty for peripheral artery disease from January 2004 through November 2006. We calculated rates of freedom from amputation, freedom from intervention, and freedom from death and examined the data using the Kaplan-Meier method. Paired t tests were used to compare the ankle-brachial indices before and after cryoplasty. The study population comprised 99 patients who received treatment for 132 atherosclerotic lesions, including 62 lesions in the superficial femoral artery, 28 in the popliteal artery, and 25 in arteries below the knee; 71 patients completed follow-up (64 ± 57 wk). Short-term periprocedural success was achieved in 98.5% of the interventions. Dissections occurred in 12.2% of patients treated successfully without bail-out stenting or additional balloon inflations. At 6 months, more than 88% of the patients were alive and had not had an amputation. However, reintervention was required for 42% of patients. Mean ankle-brachial indices improved significantly after treatment (P < 0.0001). Our results show that cryoplasty for treatment of peripheral artery disease is safe and has a high rate of periprocedural success. However, long-term efficacy is compromised because of the frequent need for reintervention.

The coronary artery calcium score and stress myocardial perfusion imaging provide independent and complementary prediction of cardiac risk.

OBJECTIVES: This study sought to examine the relationship between coronary artery calcium score (CACS) and single-photon emission computed tomography (SPECT) results for predicting the short- and long-term risk of cardiac events. BACKGROUND: The CACS and SPECT results both provide important prognostic information. It is unclear whether integrating these tests will better predict patient outcome. METHODS: We followed-up 1,126 generally asymptomatic subjects without previous cardiovascular disease who had a CACS and stress SPECT scan performed within a close time period (median 56 days). The median follow-up was 6.9 years. End points analyzed were total cardiac events and all-cause death/myocardial infarction (MI). RESULTS: An abnormal SPECT result increased with increasing CACS from <1% (CACS < or =10) to 29% (CACS >400) (p < 0.001). Total cardiac events and death/MI also increased with increasing CACS and abnormal SPECT results (p < 0.001). In subjects with a normal SPECT result, CACS added incremental prognostic information, with a 3.55-fold relative increase for any cardiac event (2.75-fold for death/MI) when the CACS was severe (>400) versus minimal (< or =10). Separation of the survival curves occurred at 3 years after initial testing for all cardiac events and at 5 years for death/MI. CONCLUSIONS: The CACS and SPECT findings are independent and complementary predictors of short- and long-term cardiac events. Despite a normal SPECT result, a severe CACS identifies subjects at high long-term cardiac risk. After a normal SPECT result, our findings support performing a CACS in patients who are at intermediate or high clinical risk for coronary artery disease to better define those who will have a high long-term risk for adverse cardiac events.

Predictors of carotid stent restenosis.

OBJECTIVES: We sought to determine the predictors of restenosis after carotid artery stenting and report alternatives for its management. BACKGROUND: Carotid artery stenting has been increasingly accepted as an alternative to carotid endarterectomy (CEA). Predictors of carotid stent restenosis have not been firmly established, and management of restenotic lesions can be challenging. METHODS: A retrospective, single-center review was conducted of 399 carotid stent procedures in 363 patients over 9 years, with a mean follow-up of 24 months (range 6-99 months). Clinical variables included age, gender, symptoms, hypertension, diabetes, tobacco use, renal insufficiency, coronary artery disease, hyperlipidemia, peripheral vascular disease, history of CEA, and history of neck radiation (XRT). Angiographic variables included reference vessel diameter, lesion length, post-stenting residual stenosis, stent diameter, type of stent, and number of stents. RESULTS: Overall, restenosis occurred in 15 patients (3.8%). However, the restenosis occurred in 7 of 35 (20%) patients who had previous XRT, 6 of 57 (10.5%) patients who had previous CEA, and 2 of 9 (22%) patients who previously had both CEA and XRT. The only analyzed variables that were significantly associated with an increased risk of restenosis were previous CEA (OR 4.28, P = 0.008) or XRT (OR 11.3, P