Two-Year Outcomes of Sacral Neuromodulation Versus OnabotulinumtoxinA for Refractory Urgency Urinary Incontinence: A Randomized Trial.

BACKGROUND: Urgency urinary incontinence (UUI) is a chronic condition for which sacral neuromodulation (SNM) (InterStim/Medtronic) and onabotulinumtoxinA (BTX) (BotoxA/Allergan) are utilized. These therapies have not been compared over extended time. OBJECTIVE: To compare UUI episodes (UUIE) over 24 mo following SNM or BTX. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, open-label, randomized, extension trial (February 2012-July 2016) at nine US medical centers involving 386 women with ≥6 UUIE over 3 d inadequately managed by medications. Participants were clinical responders to treatment: ≥50% reduction in UUIEs after SNM placement or 1 mo post BTX. INTERVENTION: SNM (n=194) versus 200 U BTX (n=192). SNM reprogrammings occurred throughout the 24 mo. After 6 mo, two additional BTX injections were allowed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Primary outcome: change in mean daily UUIE over 24 mo. SECONDARY OUTCOMES: no UUIE, ≥75% and ≥50% UUIE reduction; Overactive Bladder Questionnaire Short Form; Urinary Distress Inventory short form; Incontinence Impact Questionnaire; Patient Global Impression of Improvement; Overactive Bladder Satisfaction of Treatment Questionnaire; and adverse events (AEs). Primary analysis used a linear mixed model. RESULTS AND LIMITATIONS: Outcome data were available for 260/298 (87%) clinical responders. No difference in decreased mean UUIE was found over 24 mo (-3.88 vs -3.50 episodes/d,95% confidence interval [CI]=-0.14-0.89; p=0.15), with no differences in UUI resolution, ≥75% or ≥50% UUIE reduction. BTX group maintained higher satisfaction (mean difference=-9.14, 95% CI=-14.38--3.90; p<0.001), treatment endorsement (mean difference=-12.16, 95% CI=-17.7--6.63; p<0.001) through 24 mo. Other secondary measures did not differ. Recurrent urinary tract infections (UTIs) were higher after BTX (24% vs 10%; p<0.01), 6% required intermittent catheterization post second injection. SNM revision and removals occurred in 3% and 9% patients, respectively. CONCLUSIONS: Both treatments offered sustainable UUI improvement, and higher BTX dosing had low clean intermittent catheterization rates, but with UTI risk. SNM revision/removal rates were low due to standardized lead placement with strict treatment response definitions. PATIENT SUMMARY: We compared a large group of US women with severe urgency urinary incontinence (UUI) who received sacral neuromodulation (InterStim) or onabotulinumtoxinA (Botox A) therapy during a 2-yr period. We found that both therapies had similar success in reducing UUI symptoms, and adverse events were low. However, women in the BotoxA group had higher satisfaction and endorsement with their treatment, but with a higher chance of a urinary tract infection. We conclude that both therapies offer sustained reduction in daily incontinence over 2 yr.

Left and codominant coronary artery circulations are associated with higher in-hospital mortality among patients undergoing percutaneous coronary intervention for acute coronary syndromes: report From the National Cardiovascular Database Cath Percutaneous Coronary Intervention (CathPCI) Registry.

BACKGROUND: Left or codominant coronary arterial circulation may represent less well-balanced myocardial perfusion and thus confer worse prognosis in acute coronary syndrome, especially for culprit lesions arising from the left coronary artery. METHODS AND RESULTS: We related left and codominance, relative to right dominance, with in-hospital mortality in 207 926 percutaneous coronary interventions (PCI) for acute coronary syndromes from July 1, 2009 through June 30, 2010 in the National Cardiovascular Data Registry Cath Percutaneous Coronary Intervention (CathPCI) Registry database version 4. Generalized estimating equations and logistic regression analyses were used in unadjusted and multivariable adjusted models. Models were adjusted using the validated National Cardiovascular Data Registry mortality risk model. We performed subgroup analyses and formally tested for effect modification by the epicardial coronary artery containing the culprit lesion. Left coronary dominance was associated with higher in-hospital mortality in unadjusted (odds ratio=1.29, 95% confidence interval [CI], 1.17-1.42) and adjusted models (1.19, 95% CI, 1.06-1.34). Codominance was associated with worsened mortality only in adjusted models (odds ratio=1.16, 95% CI, 1.01-1.34). Addition of coronary dominance to the National Cardiovascular Data Registry risk model did not materially change model discrimination or calibration. The odds of death for left versus right dominance among those with left circumflex or left main culprit lesions was 1.25 (95% CI, 1.02-1.53), for right coronary artery lesions was 1.19 (95% CI, 0.83-1.71), and for left anterior descending artery lesions was 1.09 (95% CI, 0.93-1.28). There was no statistical evidence for effect modification by culprit lesion vessel (P=0.8). CONCLUSIONS: Left and codominance are associated with modestly increased post-percutaneous coronary intervention in-hospital mortality in patients with acute coronary syndrome. Confirmation of these findings with angiographic core laboratory verification of coronary dominance and longer term follow-up will be desirable.

Incidence of thrombocytopenia among patients receiving heparin venous thromboembolism prophylaxis.

BACKGROUND: Heparin is commonly used for venous thromboembolism prophylaxis; however, the incidence of acquired thrombocytopenia in this setting has not been well described. METHODS: The Complications After Thrombocytopenia Caused by Heparin (CATCH) Registry was designed to evaluate the risk of thrombocytopenia among patients receiving heparin in diverse clinical settings. We examined the incidence, management, and outcomes of thrombocytopenia (platelet count decrease ≥50% or to nadir <150×10(9)/L) among patients with normal admission platelet counts (≥150×10(9)/L) who received ≥72 hours of heparin venous thromboembolism prophylaxis. RESULTS: Among 1017 patients receiving heparin venous thromboembolism prophylaxis, 190 (19%) developed thrombocytopenia. Factors significantly associated with the development of thrombocytopenia include higher admission platelet count, ventilator use, prolonged heparin exposure, unfractionated heparin use, lower admission blood pressure, and cardiac surgery. For thrombocytopenic patients, only 5% received serologic testing for heparin-induced thrombocytopenia, and a hematology consult was obtained in 3%, but none were switched to a direct thrombin inhibitor. Acquired thrombocytopenia was not associated with increased in-hospital risk of mortality or thromboembolic events (adjusted odds ratio 1.06; 95% confidence interval, 0.57-1.95); however, it was associated with increased Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) moderate or severe bleeding risk (adjusted odds ratio 4.49; 95% confidence interval, 2.24-9.02). CONCLUSION: Thrombocytopenia occurs frequently in patients on heparin venous thromboembolism prophylaxis, yet its diagnosis has minimal impact on downstream management. The development of thrombocytopenia is associated with increased bleeding risk.

Modifiable risk factors associated with sudden cardiac arrest within hemodialysis clinics.

Sudden cardiac arrest is the most common cause of death among patients with end-stage kidney disease (ESKD) maintained on hemodialysis. Here we sought to identify dialysis-related factors associated with this increased risk in a case-control study encompassing 43,200 patients dialyzed in outpatient clinics of a large organization. Within this group, we compared the clinical and dialysis-specific data of 502 patients who experienced a sudden cardiac arrest with 1632 age- and dialysis-vintage-matched controls. There were 4.5 sudden cardiac arrest events per 100,000 dialysis treatments during the 3-year study period. These patients were significantly more likely to have been exposed to low potassium dialysate of less than 2 meq/l. These differences could not be explained by predialysis serum potassium levels. There was no evidence for a beneficial effect of low potassium dialysate even among those with higher predialysis serum potassium levels. Other factors strongly associated with sudden cardiac arrest by multivariable analysis included increased ultrafiltration volumes, exposure to low calcium dialysate, and predialysis serum creatinine levels. These relationships persisted after adjustment for covariates, but traditional risk factors such as history of coronary heart disease and congestive heart failure were not significantly influential. Hence, our study suggests that modifications of the hemodialysis prescription may improve the risk of sudden cardiac arrest in patients with ESKD.

Influence of patient age on procedural selection in mitral valve surgery.

BACKGROUND: Previous studies suggest that mitral valve replacement is comparable to repair in the elderly, and a national trend exists toward tissue valves. However, few direct comparison data are available, and this study evaluated the effects of patient age on risk-adjusted survival after mitral procedures. METHODS: From 1986 to 2006, 2,064 patients underwent isolated primary mitral operations (±CABG). Maximal follow-up was 20 years with a median of 5 years. Valve disease etiology was the following: degenerative, 864; ischemic, 450; rheumatic, 416; endocarditis, 98; and "other," 236. Overall, 58% had repair and 39% had concomitant coronary artery bypass grafting. Survival differences were evaluated with a Cox proportional hazards model that included baseline characteristics, valve disease etiology, and choice of repair versus replacement with tissue or mechanical valves. RESULTS: Baseline risk profiles generally were better for mechanical valves, and age was the most significant multivariable predictor of late mortality [hazard ratio = 1.4 per 10-year increment, Wald χ(2) = 32.7, p < 0.0001]. As compared with repair, risk-adjusted survival was inferior with either tissue valves [1.8, 27.6, <0.0001] or mechanical valves [1.3, 8.1, 0.0044], and no treatment interaction was observed with age (p = 0.18). At no patient age did tissue valves achieve equivalent survival to either repair or mechanical valves. CONCLUSIONS: Mitral repair is associated with better survival than valve replacement across the spectrum of patient age. If replacement is required, mechanical valves achieve better outcomes, even in the elderly. These data suggest that tissue valves should be reserved only for patients with absolute contraindications to anticoagulation who are not amenable to repair.

Economic assessment of thrombocytopenia: CATCH Registry.

Thrombocytopenia is associated with increased patient risk. However, the costs of this complication are not well defined. This study assessed the impact of thrombocytopenia on in-hospital costs using results from CATCH, an observational study that examined 1988 consecutive patients receiving prolonged heparin therapy (> or =96 h). Thrombocytopenia was defined as: (group 1) an absolute reduction in platelet count to <150 x 10(9)/L; (group 2) a relative reduction in platelet count of >50% from admission levels; or (group 3) both criteria. We found that the development of thrombocytopenia was associated with significantly higher total in-hospital costs for all groups: (group 1) (difference, $8,222; 95% CI, $5,020-$11,425; P<.001); (group 2) (difference, $15,429; 95% CI, $7,472-$23,385; P<.001); and (group 3) (difference, $27,077; 95% CI, $22,901-$31,252; P<.001). However, in our adjusted model, longer lengths-of-stay and greater use of blood transfusions accounted for most incremental in-hospital cost differences.

Mitral valve repair for degenerative disease: a 20-year experience.

BACKGROUND: Recent advances in surgical technique allow repair of most mitral valves with degenerative disease. However, few long-term data exist to support the superiority of repair versus prosthetic valve replacement, and repair could be limited by late durability or other problems. This study was designed to compare survival characteristics of mitral valve repair versus prosthetic replacement for degenerative disorders during a 20-year period. METHODS: From 1986 to 2006, 2,580 patients underwent isolated mitral valve procedures (with or without coronary artery bypass grafting), with 989 classified as having degenerative origin. Of these, 705 received valve repair, and 284 had prosthetic valve replacement. Differences in baseline characteristics between groups were assessed, and unadjusted survival estimates were generated using Kaplan-Meier methods. Survival curves were examined after adjustment for differences in baseline profiles using a Cox model, and average adjusted survival differences were quantified by area under the curve methodology. Survival differences during 15 years of follow-up also were assessed with propensity matching. RESULTS: Baseline characteristics were similar, except for (variable: repair, replacement) age: 62 years, 68 years; concomitant coronary artery bypass grafting: 24%, 32%; ejection fraction: 0.51, 0.55; congestive heart failure: 68%, 43%; and preoperative arrhythmia: 11%, 7% (all p < 0.05). Long-term survival was significantly better in the repair group, both for unadjusted data (p < 0.001) and for risk-adjusted results (p = 0.040). Patient survival in the course of 15 years averaged 7.3% better with repair, and increased with time of follow-up: 0.7% better for 0 to 5 years, 4.9% better for 5 to 10 years, and 21.3% better for 10 to 15 years. Treatment interaction between repair or replacement and age was negative (p = 0.66). In the propensity analysis, survival advantages of repair versus replacement were similar in magnitude with a p value of 0.046. CONCLUSIONS: As compared with prosthetic valve replacement, mitral repair is associated with better survival in patients with degenerative disease, especially after 10 to 15 years. This finding supports the current trend of increasing repair rates for degenerative disorders of the mitral valve.

Six-month follow-up of patients with in-hospital thrombocytopenia during heparin-based anticoagulation (from the Complications After Thrombocytopenia Caused by Heparin [CATCH] registry).

Thrombocytopenia is a predictor of adverse outcomes in patients with acute coronary syndromes and in critically ill patients. The Complications After Thrombocytopenia Caused by Heparin (CATCH) registry was designed to explore the incidence, management, and clinical consequences of in-hospital thrombocytopenia occurring during heparin-based anticoagulation in diverse clinical settings. We conducted a prospective observational study of 37 United States hospitals participating in the CATCH registry to assess the relation of in-hospital thrombocytopenia to long-term outcomes. A total of 2,104 patients at increased risk of developing in-hospital thrombocytopenia or thrombosis were identified, and the 6-month mortality and rehospitalization rates were determined. Thrombocytopenia was not a significant predictor of 6-month mortality. In an adjusted model for in-hospital death in this cohort, thrombocytopenia had an odds ratio of 3.59 (95% confidence interval 2.24 to 5.77). The postdischarge mortality rate at 6 months was 9.7%. No significant difference was observed in the long-term mortality between patients who developed thrombocytopenia and those who did not. Thrombocytopenia was a weak, but statistically significant, predictor of a composite of mortality and rehospitalization at 6 months (hazards ratio 0.80, 95% confidence interval 0.65 to 0.98, p = 0.03). In conclusion, the 6-month mortality rate among heparin-treated patients with thrombocytopenia is high, although the risk independently related to thrombocytopenia appears to be restricted to the acute hospital phase.

Chronic kidney disease is associated with increased risk of sudden cardiac death among patients with coronary artery disease.

Sudden cardiac death is the most common cause of mortality among patients with end-stage kidney disease maintained on hemodialysis. To examine whether this increased risk is also seen with less advanced kidney disease, we studied the relationship between glomerular filtration rate and risk of sudden cardiac death in patients with moderate kidney disease and known coronary artery disease. This retrospective longitudinal study encompassed 19,440 consecutive patients who underwent cardiac catheterization at a single academic institution. There were 522 adjudicated sudden cardiac death events, yielding an overall rate of 4.6 events per 1000 patient years. This figure reflected rates of 3.8 events in 14,652 patients with estimated glomerular filtration rates (eGFR) > or =60 (stage 2 CKD or better) and 7.9 events in 4788 patients with glomerular filtration rates <60 (stage 3-5 CKD), all normalized to 1000 patient-years. After adjusting for differences in known cardiac risk factors and other covariates in a multivariate Cox proportional hazards model, the eGFR was independently associated with sudden cardiac death (hazard ratio (HR)=1.11 per 10 ml/min decline in the eGFR). Our analysis found that reductions in the eGFR in CKD stages 3-5 are associated with a progressive increase in risk of sudden cardiac death in patients with coronary artery disease. Additional studies are needed to better characterize the mechanisms by which reduced kidney function increases this risk.

Evaluation and management of thrombocytopenia and suspected heparin-induced thrombocytopenia in hospitalized patients: The Complications After Thrombocytopenia Caused by Heparin (CATCH) registry.

BACKGROUND: Thrombocytopenia and heparin-induced thrombocytopenia (HIT) are potentially devastating paradoxical side effects of heparin therapy. We explored the evaluation, management, and clinical consequences of thrombocytopenia occurring during heparin therapy in diverse clinical settings. METHODS: CATCH was a prospective observational study that enrolled 3,536 patients in 48 US hospitals. Data were collected on 3 strata: patients receiving any form of heparin for > or =96 hours (n = 2,420); cardiac care unit (CCU) patients treated with heparin who developed thrombocytopenia (n = 1,090); patients who had an HIT assay performed (n = 449). RESULTS: Thrombocytopenia occurred in 36.4% of patients in the prolonged heparin stratum and was associated with an increased risk of death or thromboembolic complication (OR 1.5, 95% CI 1.2-1.9). Among a subset of patients whose clinical presentation suggested they were at high risk for HIT, suspicion for HIT was uncommon (prolonged heparin stratum 19.8%, CCU stratum 37.6%) and often did not arise until > or =1 day after patients developed thrombocytopenia. Often patients were not evaluated for HIT until after they had had a thromboembolic complication (prolonged heparin stratum 43.8%, CCU stratum 61%). Even after HIT was suspected, patients often continued to receive heparin. Direct thrombin inhibitor use was infrequent (prolonged heparin stratum 29.4%, CCU stratum 35.6%). Among the few patients who underwent evaluation, HIT was confirmed in 46.7% of the prolonged heparin stratum and 31.4% of the CCU stratum. CONCLUSIONS: Thrombocytopenia is common among patients receiving heparin, and it is associated with substantial risk for catastrophic complications. Despite the high risk for HIT in this population, recognition, evaluation, and appropriate treatment are infrequent and delayed.

Evaluation of mechanical dyssynchrony and myocardial perfusion using phase analysis of gated SPECT imaging in patients with left ventricular dysfunction.

BACKGROUND: Using phase analysis of gated single photon emission computed tomography (SPECT) imaging, we examined the relation between myocardial perfusion, degree of electrical dyssynchrony, and degree of SPECT-derived mechanical dyssynchrony in patients with left ventricular (LV) dysfunction. METHODS AND RESULTS: We retrospectively examined 125 patients with LV dysfunction and ejection fraction of 35% or lower. Fourier analysis converts regional myocardial counts into a continuous thickening function, allowing resolution of phase of onset of myocardial thickening. The SD of LV phase distribution (phase SD) and histogram bandwidth describe LV phase dispersion as a measure of dyssynchrony. Heart failure (HF) patients with perfusion abnormalities have higher degrees of dyssynchrony measured by median phase SD (45.5 degrees vs 27.7 degrees, P < .0001) and bandwidth (117.0 degrees vs 73.0 degrees, P = .0006). HF patients with prolonged QRS durations have higher degrees of dyssynchrony measured by median phase SD (54.1 degrees vs 34.7 degrees, P < .0001) and bandwidth (136.5 degrees vs 99.0 degrees, P = .0005). Mild to moderate correlations exist between QRS duration and phase analysis indices of phase SD (r = 0.50) and bandwidth (r = 0.40). Mechanical dyssynchrony (phase SD >43 degrees) was 43.2%. CONCLUSIONS: HF patients with perfusion abnormalities or prolonged QRS durations have higher degrees of mechanical dyssynchrony. Gated SPECT myocardial perfusion imaging can quantify myocardial function, perfusion, and dyssynchrony and may help in evaluating patients for cardiac resynchronization therapy.

Evaluation of combined cardiac positron emission tomography and coronary computed tomography angiography for the detection of coronary artery disease.

BACKGROUND: Coronary artery disease is a leading cause of morbidity and mortality. Multiple imaging modalities are used to screen for significant coronary artery disease. We report the concordance between coronary computed tomography angiography (CTA) and stress cardiac positron emission tomography (CPET) to detect significant coronary artery disease, the feasibility of combining CTA and CPET in one diagnostic test, and the ability of CTA and CPET to detect significant coronary artery disease by comparison with cardiac catheterization. METHODS: Forty patients were prospectively enrolled and imaged with a hybrid PET/CT scanner. Eighteen patients had cardiac catheterization data for comparison. Concordance of findings between diagnostic tests was assessed by examining overall percentage in agreement, area under the receiver operating characteristic curve, sensitivity, specificity, and positive and negative predictive values. RESULTS: The overall agreement between CTA and CPET for detecting significant coronary artery disease was 76.3% with a sensitivity and specificity of 91.7 and 69.2%, respectively. The overall agreement between CTA and cardiac catheterization for detecting significant coronary artery disease was 81.3% with a sensitivity and specificity of 81.8 and 80.0%, respectively. The overall agreement between CPET and cardiac catheterization for detecting significant coronary artery disease was 77.8% with a sensitivity and specificity of 76.9 and 80.0%, respectively. CONCLUSION: CTA and CPET can be performed in a single diagnostic test interval to simultaneously assess the extent of coronary artery disease and its hemodynamic significance. The sensitivity and specificity of CTA and CPET are similar to existing noninvasive screening tests.

Repeatability and reproducibility of phase analysis of gated single-photon emission computed tomography myocardial perfusion imaging used to quantify cardiac dyssynchrony.

BACKGROUND: A novel method to quantify dyssynchrony has been developed using phase analysis of gated single-photon emission computed tomography perfusion imaging. We report on the effect of variability in image reconstruction on the phase analysis results (repeatability) and on the interobserver and intraobserver reproducibility of the technique. METHODS: Phase standard deviation (SD) and bandwidth are phase indices that quantify dyssynchrony. To evaluate repeatability, raw data sets were processed twice in 50 patients with left ventricular dysfunction and 50 normal controls. To determine the optimal processing method, two replicated phase analysis results were obtained using automated and manual base parameter placement. Reproducibility of the phase analysis was determined using the data from 20 patients. RESULTS: In normal controls, manual base parameter placement improves repeatability of the phase analysis as measured by the mean absolute difference between two reads for phase SD (12.0 degrees vs. 1.2 degrees , P<0.0001) and bandwidth (33.7 degrees vs. 3.6 degrees , P<0.0001). Repeatability is better for normal controls than for patients with left ventricular dysfunction for phase SD (1.2 degrees vs. 6.0 degrees , P<0.0001) and bandwidth (3.6 degrees vs. 26.5 degrees , P<0.0001). Reproducibility of the phase analysis is high as measured by the intraclass correlation coefficients for phase SD and bandwidth of 0.99 and 0.99 for the interobserver comparisons and 1.00 and 1.00 for the intraobserver comparisons. CONCLUSION: A novel method to quantify dyssynchrony has been developed using gated single-photon emission computed tomography perfusion imaging. Manual base parameter placement reduces the effect that variability in image reconstruction has on phase analysis. A high degree of reproducibility of phase analysis is observed.

Incidence and prognostic significance of thrombocytopenia in patients treated with prolonged heparin therapy.

BACKGROUND: Despite widespread heparin use in clinical practice, the associated development of thrombocytopenia is an underrecognized and undertreated complication. METHODS: We analyzed data from consecutive hospitalized patients treated with heparin (unfractionated or low molecular weight) for 4 days or longer to determine the incidence, predictors, prognostic significance, and management of "thrombocytopenia," defined as a platelet count less than 150 x 10(9)/L, reduction in platelet count of 50% or more from the admission level, or both. RESULTS: We enrolled 2420 patients (median age, 65.2 years; 43.8% women) in 48 US hospitals. Thrombocytopenia occurred in 881 patients (36.4%; 95% confidence interval [CI], 34.5%-38.3%). Of those who developed thrombocytopenia, 5.1% died, compared with 1.6% of those without thrombocytopenia (odds ratio [OR], 3.4; 95% CI, 2.1-5.6; P< .001). Thrombocytopenia was also associated with greater risk of myocardial infarction (OR, 2.1; 95% CI, 1.5-2.8; P< .001) and congestive heart failure (OR, 1.3; 95% CI, 1.1-1.6; P= .01). After adjustment for important covariates, thrombocytopenia remained an independent predictor of thrombotic and hemorrhagic events. A relative reduction in platelet count of more than 70% was the strongest independent predictor of death (OR, 13.4; 95% CI, 6.5-27.6; P< .001), followed by a relative reduction in platelet count of 50% to 70%, worse Killip class, occurrence of thromboembolic complications, older age, and longer duration of heparin therapy. CONCLUSIONS: Thrombocytopenia occurs frequently after prolonged heparin therapy and is strongly associated with worse short-term clinical outcome. The relative reduction in platelet count is a powerful independent predictor of all-cause mortality in hospitalized patients.

Incidence and Prognostic Significance of Thrombocytopenia in Patients Treated With Prolonged Heparin Therapy / Incidence and Prognostic Significance of Thrombocytopenia in Patients Treated With Prolonged Heparin Therapy

Despite widespread heparin use in clinical practice, the associated development of thrombocitopenia is an underrecognized and undertreaded complication. Methods:We analized data from consective hospitalized patients treated with heparin (unfractionated or low molecular weight) for four days or longer to determine the incidence, predictors, prognostic significance, and management of thrombocitopenia, defined as a platelet count less than 150x10/L, reduction in platelet count of 50% or more from teh admission level, or both...

Evaluation of left ventricular mechanical dyssynchrony as determined by phase analysis of ECG-gated SPECT myocardial perfusion imaging in patients with left ventricular dysfunction and conduction disturbances.

BACKGROUND: Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients with left ventricular dysfunction, conduction delays, and ventricular paced rhythms. METHODS AND RESULTS: A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images. Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD, bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction (n = 120), left bundle branch block (n = 33), right bundle branch block (n = 19), and ventricular paced rhythms (n = 23) and were compared with normal control subjects (n = 157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms and normal control subjects (all P < .001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects (P = .001). CONCLUSIONS: A novel SPECT technique for describing left ventricular mechanical dyssynchrony has been developed and may prove useful in the evaluation of patients for CRT.

Effect of medical management on recurrent stone formation following percutaneous nephrolithotomy.

PURPOSE: Percutaneous nephrolithotomy is a commonly used procedure for treatment of large or complex renal calculi. In some instances postoperative residual stone fragments are an unavoidable result. Yet to our knowledge no study has examined the impact of medical management on stone formation in patients with or without residual fragments following percutaneous nephrolithotomy. Thus, we have conducted the first investigation of aggressive medical management following percutaneous nephrolithotomy and its impact on stone formation rates in patients with and without residual fragments. MATERIALS AND METHODS: A total of 70 patients who underwent percutaneous nephrolithotomy and received counseling regarding selective medical management following a comprehensive metabolic evaluation, were identified. Patients were placed into 4 groups following percutaneous nephrolithotomy, that is stone-free or residual fragments, who underwent or did not undergo medical therapy. New stone formation was assessed by spontaneous stone passage in the absence of residual stone fragments, stone passage without change in the number of residual fragments, surgical removal of newly formed stones, or appearance of new stones or increase in size of stone or fragments on abdominal radiographs. Stone remission rates were also calculated. RESULTS: Selective medical therapy significantly decreased stone formation rates in the stone-free (0.67 stones per patient per year vs 0.02) and residual fragment groups (0.67 stones per patient per year vs 0.02) as determined by the Wilcoxon signed rank test (p<0.0001). Moreover, remission was observed in a higher proportion of patients in the medically treated stone-free and residual fragment groups (87% and 77%) when compared to the same groups without medical therapy (29% and 21%, chi-square test p<0.0001). CONCLUSIONS: Our findings suggest that comprehensive metabolic evaluation and aggressive medical management can control active stone formation and growth in patients with or without residual stone fragments after percutaneous nephrolithotomy. Given the inherent morbidity and increased costs attendant with repeat procedures, medical management should be instituted in patients following percutaneous nephrolithotomy without regard to stone-free status.

Acute myocardial infarction: safety of cardiac MR imaging after percutaneous revascularization with stents.

PURPOSE: To retrospectively determine the safety of cardiac magnetic resonance (MR) imaging performed early (<14 days) after coronary stent implantation in patients with acute myocardial infarction (AMI). MATERIALS AND METHODS: This HIPPA-compliant study was approved by the institutional review board; the informed consent requirement was waived. Consecutive patients with AMI who underwent cardiac MR imaging (study group) shortly after stent implantation (median, 3 days) were compared with control subjects who did not undergo MR imaging and were matched for clinical factors and angiographic extent of coronary disease. A 1.5-T MR imager was used to evaluate cine function, perfusion, and viability. Rates of death, nonfatal myocardial infarction, or revascularization 30 days and 6 months after stent implantation were compared with chi(2) analysis. RESULTS: The study group consisted of 66 patients (median age, 56 years; 17 women) with 97 stents, 38 (39%) of which were drug eluting. The control group included 124 patients (median age, 58 years; 23% women) with 197 stents, 21 (10.7%) of which were drug eluting. There was no significant (P = .13) difference in the combined end point of death, nonfatal myocardial infarction, or revascularization between the study (2.0% [95% confidence interval: 0.0%, 4.5%]) and control (6.5% [95% confidence interval: 1.6%, 11.3%]) groups at 30-day follow-up. The event-free survival rate at 6-month follow-up was 91% in the study group and 83.7% in the control group (P = .18). Considering the end points separately, there was no difference in the event rate at 30-day or 6-month follow-up between groups. No adverse cardiovascular events occurred in patients with drug-eluting stents who underwent MR imaging. CONCLUSION: Cardiac MR imaging performed shortly after AMI and percutaneous revascularization with bare metal or drug-eluting stents appears safe. The risk of adverse cardiovascular events is low and similar to that in patients who do not undergo MR imaging.