Integration of 3D nuclear imaging in 3D mapping system for ventricular tachycardia ablation in patients with implanted devices: Perfusion/voltage retrospective assessment of scar location.

Background: The identification of low-voltage proarrhythmic areas for catheter ablation of scar-mediated ventricular tachycardia (VT) remains challenging. Integration of myocardial perfusion imaging (single-photon emission computed tomography/computed tomography; SPECT/CT) and electroanatomical mapping (EAM) may improve delineation of the arrhythmogenic substrate. Objective: To assess the feasibility of SPECT/CT image integration with voltage maps using the EnSite Precision system (Abbott) in patients undergoing scar-mediated VT ablation. Methods: Patients underwent SPECT/CT imaging prior to left ventricular (LV) EAM with the EnSite Precision mapping system. The SPECT/CT, EAM data, and ablation lesions were retrospectively co-registered in the EnSite Precision system and exported for analysis. Segmental tissue viability scores were calculated based on SPECT/CT perfusion and electrogram bipolar voltage amplitude. Concordance, specificity, and sensitivity between the 2 modalities as well as the impact of SPECT/CT spatial resolution were evaluated. Results: Twenty subjects (95% male, 67 ± 7 years old, left ventricular ejection fraction 36% ± 11%) underwent EAM and SPECT/CT integration. A concordance of 70% was found between EAM and SPECT/CT for identification of cardiac segments as scar vs viable, with EAM showing a 68.5% sensitivity and 76.4% specificity when using SPECT/CT as a gold standard. Projection on low-resolution 3D geometries led to an average decrease of 38% ± 22% of the voltage points used. Conclusion: The study demonstrated the feasibility of integrating SPECT/CT with EAM performed retrospectively for characterization of anatomical substrates during VT ablation procedures.

Assessment of left ventricular ejection fraction with cardiofocal collimators: Comparison between IQ-SPECT, planar equilibrium radionuclide angiography, and cardiac magnetic resonance.

BACKGROUND: IQ-SPECT has been shown to significantly reduce acquisition time and administered dose while preserving image quality in myocardial perfusion imaging. Whether IQ-SPECT provides accurate left ventricular ejection fractions (LVEF) with gated blood pool SPECT (GBPS) remains unknown. METHODS: Sixty patients underwent IQ-SPECT GBPS and planar imaging. Among those patients, 11 underwent both cMRI and GBPS. GBPS LVEF, LVEDV, and LVESV were calculated using 2 validated software; QBS (Cedars-Sinai Medical Center, Los Angeles, USA) and MHI (Montreal Heart Institute, Montreal, Canada). LVEF, LVEDV, and LVESV obtained with the different modalities were compared. RESULTS: Average planar LVEF was 48 ± 11% (mean ± SD), average LVEDV was 177 ± 59 mL (range 63 to 342 mL), and average LVESV was 96 ± 46 mL (range 16 to 234 mL). GBPS LVEF and their correlation coefficient with planar LVEF were 40 ± 12% (r = 0.70) and 44 ± 12% (r = 0.83) with QBS and MHI, respectively. Correlation coefficient between cMRI and planar LVEF was 0.65 and were 0.69 and 0.52 between cMRI and GBPS using QBS and MHI, respectively. CONCLUSIONS: LVEF calculated with GBPS using IQ-SPECT correlates with planar measurements. Correlation is best using the MHI method and variation is independent of LVEDV.

The trajectory of palliative care costs over the last 5 months of life: a Canadian longitudinal study.

OBJECTIVE: This study aimed to highlight the trajectory of palliative care costs over the last five months of life in five urban centres across Canada. SUBJECTS: The study sample was comprised of 160 terminally ill patients and their main informal caregivers. RESEARCH DESIGN: A first interview took place in the patient's home, and subsequent follow-up interviews were conducted by telephone at two week intervals until the patient's passing. MEASURES: Participants were asked to provide information on the goods and services they used related to the patients' health condition, and on informal caregiving time. RESULTS: The overall costs of care gradually increased from the fifth to the last month of the patients' life. A large part of this cost increase was attributable to inpatient care. Among outpatient care costs the largest increase was observed for home care. Informal care costs were particularly high over the last 3 months of life. CONCLUSIONS: The knowledge gained from this study would be useful to policy makers when developing policies that could help families caring for a terminally ill loved one at home.

Gated blood-pool SPECT versus cardiac magnetic resonance imaging for the assessment of left ventricular volumes and ejection fraction.

BACKGROUND: We evaluated the accuracy of planar radionuclide angiography and different count-based and space-based electrocardiogram (ECG)-gated blood-pool single-photon emission computed tomography (GBPS) algorithms for assessment of left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) compared with the gold standard of cardiac magnetic resonance imaging (cMRI). The goal is to assess the accuracy of a recently developed GBPS algorithm. METHODS AND RESULTS: Subjects had planar, GBPS, and cMRI sequentially. Datasets were processed by QBS software (Cedar-Sinai) and by MHI software (Montreal Heart Institute). Space-based approaches were used to compute LVEDV, LVESV, and LVEF. Count-based techniques were also used to assess LVEF. All results were compared to cMRI. Fifty-five patients (85% male; mean age 63 +/- 9 years) completed the study. LVEFs and their correlations to cMRI values were 43 +/- 12% (r = .82), 39 +/- 14% (r = .82), and 39 +/- 13% for MHI(space), QBS(space), and cMRI methodologies, respectively. LVEF by count-based methods also demonstrated good correlation to LVEF provided by cMRI (42 +/- 13%, r = .88 for MHI(count) and 46 +/- 15%, r = .84 for QBS(count)). Strong correlations were obtained for LVEDV (r = .96 for MHI and r = .92 for QBS) and for LVESV (.97 for MHI and r = .94 for QBS). CONCLUSIONS: All Gated blood-pool SPECT algorithms had significant variation in estimating LVEF. Nevertheless our software provides good estimates of LV volumes and LVEF. Such software may, therefore, be applied to assess LV morphology and function.

Costs associated with resource utilization during the palliative phase of care: a Canadian perspective.

OBJECTIVE: This study aimed to evaluate prospectively the resource utilization and related costs during the palliative phase of care in five regions across Canada. SUBJECTS: A cohort of 248 patients registered in a palliative care program and their main informal caregivers were consecutively recruited. RESEARCH DESIGN: A prospective research design with repeated measures was adopted. Interviews were conducted at two-week intervals until the patient s passing or up to a maximum of 6 months. MEASURES: The survey questions prompted participants to provide information on the types and number of goods and services they used, and who paid for these goods and services. RESULTS: The largest cost component for study participants was inpatient hospital care stays, followed by home care and informal caregiving time. In regard to cost sharing, the public health care system (PHCS), the family, and not-for-profit organizations (NFPO) sustained respectively 71.3%, 26.6%, and 1.6% of the mean total cost per patient. CONCLUSION: Such results provide a comprehensive picture of costs related to palliative care in Canada, by specifying the cost sharing between the PHCS, the family, and NFPO.

Fast, systematic, and continuous delirium assessment in hospitalized patients: the nursing delirium screening scale.

Because no rigorously validated, simple yet accurate continuous delirium assessment instrument exists, we developed the Nursing Delirium Screening Scale (Nu-DESC). The Nu-DESC is an observational five-item scale that can be completed quickly. To test the validity of the Nu-DESC, 146 consecutive hospitalized patients from a prospective cohort study were continuously assessed for delirium symptoms by bedside nurses using the Nu-DESC. Psychometric properties of Nu-DESC screening were established using 59 blinded Confusion Assessment Method (CAM) ratings made by research nurses and psychiatrists. DSM-IV criteria and the Memorial Delirium Assessment Scale (MDAS) were rated along with CAM assessments. Analysis of these data showed that the Nu-DESC is psychometrically valid and has a sensitivity and specificity of 85.7% and 86.8%, respectively. These values are comparable to those of the MDAS, a longer instrument. Nu-DESC and DSM-IV sensitivities were similar. The Nu-DESC appears to be well-suited for widespread clinical use in busy oncology inpatient settings and shows promise as a research instrument.