Pasalic, Dario

Abstract Objective : Blood flow waveforms—essential data for hemodynamic modeling—are often in practice unavailable to researchers. The objectives of this work were to assess the variability among the waveforms for a clinically relevant older population, and develop data-based methods for addressing the missing waveform data for hemodynamic studies. Approach : We analyzed 272 flow waveforms from the internal carotid arteries of older patients (73 ± 13 yr) with moderate cardiovascular disease, and used these data to develop methods to guide new approaches for hemodynamic studies. Main results : Profound variations in waveform parameters were found within the aged population that were not seen in published data for young subjects. Common features in the aged population relative to the young included a larger systole-to-diastole flow rate ratio, increased flow during late systole, and absence of a dicrotic notch. Eight waveforms were identified that collectively represent the range of waveforms in the older population. A relationship between waveform shape and flow rate was obtained that, in conjunction with equations relating flow rate to diameter, can be used to provide individualized waveforms for patient-specific geometries. The dependence of flow rate on diameter was statistically different between male and female patients. Significance : It was shown that a single archetypal waveform cannot well-represent the diverse waveforms found within an aged population, although this approach is frequently used in studies of flow in the cerebral vasculature. Motivated by these results, we provided a set of eight waveforms that can be used to assess the hemodynamic uncertainty associated with the lack of patient-specific waveform data. We also provided a methodology for generating individualized waveforms when patient gender, age, and cardiovascular disease state are known. These data-driven approaches can be used to devise more relevant in vitro or in silico intra-cranial hemodynamic studies for older patients.

The presence of cardiac pacemakers and defibrillators complicates making end-of-life (EOL) medical decisions. Palliative care/medicine consultation (PCMC) may benefit patients and primary providers, but data are lacking. We retrospectively reviewed 150 charts of patients who underwent device deactivation at our tertiary care center (between November 1, 2008, and September 1, 2012), assessing for PCMC and outcomes. Overall, 42% of patients received a PCMC, and 68% of those PCMCs specifically addressed device deactivation. Median survival following deactivation was 2 days, with 42% of deaths occurring within 1 day of deactivation. There was no difference in survival between the groups. The EOL care for patients with implanted cardiac devices is complex, but PCMC may assist with symptom management and clarification of goals of care for such patients.

BackgroundLittle is known about the use of advance directives (ADs) in patients who have implantable cardiac pacemakers (PMs).MethodsWe conducted a retrospective review of the medical records of residents of Olmsted County, Minnesota, who underwent implantation of a cardiac PM at Mayo Clinic (Rochester, Minnesota) during 2006 and 2007, and determined the prevalence and contents of ADs in these patients.ResultsDuring the study period, 205 residents of Olmsted County (men, 53%) underwent PM implantation (mean age [standard deviation] at implantation, 77 [15] years). Overall, 120 patients (59%) had ADs. Of these, 63 ADs (53%) were executed more than 12 months before and 33 (28%) were executed after PM implantation. Many patients specifically mentioned life‐prolonging treatments in their ADs: cardiopulmonary resuscitation, 76 (63%); mechanical ventilation, 56 (47%); and hemodialysis, 31 (26%). Pain control was mentioned in 79 ADs (66%) and comfort measures were mentioned in 42 ADs (35%). Furthermore, the AD of many patients contained a general statement about end‐of‐life care (e.g., no “heroic measures”). However, only one AD (1%) specifically addressed the end‐of‐life management of the PM.ConclusionsMore than half of the patients with PMs in our study had executed an AD, but only one patient specifically mentioned her PM in her AD. These results suggest that patients with PMs should be encouraged to execute ADs and specifically address end‐of‐life device management in their ADs. Doing so may prevent end‐of‐life ethical dilemmas related to PM management.

Central nervous system metastases as the presentation of primary cardiac sarcoma are a very rare entity, with only a few previously reported cases. Sarcomas specifically make up 10 to 20% of all primary cardiac tumors. Patients with primary cardiac tumors typically present with cardiac symptomatology that may include arrhythmias, obstruction to blood flow and valve function, or symptoms of heart failure. We report a unique case of a patient with a primary cardiac sarcoma who presented with progressive neurologic dysfunction secondary to brain metastases without any preceding cardiac symptoms. We describe our novel management of these unique cases and discuss the current medical and surgical approaches to treating neurologic metastases from cardiac sarcoma.