PurposeHeart transplantation causes denervation of the donor heart, but the consequences for cardiovascular homeostasis remain to be fully understood. The present study investigated cardiovascular autonomic control at supine rest, during orthostatic challenge and during isometric exercise in heart transplant recipients (HTxR).MethodsA total of 50 HTxRs were investigated 7–12 weeks after transplant surgery and compared with 50 healthy control subjects. Continuous, noninvasive recordings of cardiovascular variables were carried out at supine rest, during 15 min of 60° head-up tilt and during 1 min of 30% of maximal voluntary handgrip. Plasma and urine catecholamines were assayed, and symptoms were charted.ResultsAt supine rest, heart rate, blood pressures and total peripheral resistance were higher, and stroke volume and end diastolic volume were lower in the HTxR group. During tilt, heart rate, blood pressures and total peripheral resistance increased less, and stroke volume and end diastolic volume decreased less. During handgrip, heart rate and cardiac output increased less, and stroke volume and end diastolic volume decreased less. Orthostatic symptoms were similar across the groups, but the HTxRs complained more of pale and cold hands.ConclusionHTxRs are characterized by elevated blood pressures and total peripheral resistance at supine rest as well as attenuated blood pressures and total peripheral resistance responses during orthostatic challenge, possibly caused by low-pressure cardiopulmonary baroreceptor denervation. In addition, HTxRs show attenuated cardiac output response during isometric exercise due to efferent sympathetic denervation. These physiological limitations might have negative functional consequences.
Background The identification and treatment of psychiatric disorders in individuals with autism spectrum disorders (ASD) and ID presents many challenges. We describe the development of a professional network, together with a standardized protocol for clinical assessment, designed to promote clinical competence and professional development in eight clinical centers responsible for providing mental health services to autistic individuals with ID across all four health regions of Norway. Specific aims to describe: (1) patterns of psychiatric and behavior problems in patients treated by the network, (2) patterns of change over time, and (3) the relationship between psychiatric disorders and behavior problems. Method A standardized protocol was used to assess individual progress in 132 patients (inpatients and outpatients) with autism and ID over 2 years (at referral (T1), after 1 year (T2), and after 2 years (T3)). Changes in psychiatric symptoms and behavior problems were assessed with the Psychopathology in Autism Checklist (PAC) and Aberrant Behavior Checklist (ABC). Results Patients showed significant (p < .001) improvements from T1 to T2 on the psychosis, depression and anxiety subscales of the PAC, but no significant improvement on the obsessive compulsive disorder (OCD) subscale. Improvements were maintained from T2 to T3. Patients showed significant (p < .01) improvements on the ABC total score and on all ABC subscales except inappropriate speech from T1 to T2; these improvements were maintained from T2 to T3. Discussion The combination of a professional network and a standardized protocol for clinical assessment has promise as a strategy for improving professional competence and facilitating specialized mental health services for autistic individuals with ID and psychiatric disorders across an extensive geographical area.
Background. Heart transplantation (HTx) surgically transects all connections to the heart, including the autonomic nerves. We prospectively examined signs, timing and consequences of early sympathetic and parasympathetic sinoatrial reinnervation, as well as explored indirect evidence of afferent cardiopulmonary reinnervation. Methods. Fifty HTx recipients were assessed at 2.5, 6, and 12 mo after HTx. For comparison, 50 healthy controls were examined once. Continuous, noninvasive recordings of hemodynamic variables and heart rate variability indices were performed at supine rest, 0.2 Hz controlled breathing, 60° head-up-tilt, during the Valsalva maneuver and during handgrip isometric exercise. Results. In HTx recipients, supine low-frequency heart rate variability gradually increased; supine high-frequency variability did not change; heart rate variability indices during controlled breathing remained unaltered; heart rate responses during tilt and isometric exercise gradually increased; the tachycardia response during Valsalva maneuver increased, while the bradycardia response remained unchanged; and indices of baroreflex sensitivity improved. Responses remained low compared to healthy controls. A negative correlation between indices of preload and heart rate response during head-up tilt emerged at 12 mo. Conclusions. Results suggest that sympathetic reinnervation of the sinoatrial node starts within 6 mo after HTx and strengthens during the first year. No evidence of early parasympathetic reinnervation was found. Indirect signs of afferent reinnervation of cardiopulmonary low-pressure baroreceptors emerged at 12 mo. Better sympathetic sinoatrial control improved heart rate responsiveness to orthostatic challenge and isometric exercise, as well as heart rate buffering of blood pressure fluctuations.
Prenatal ductal constriction and closure usually are related to maternal intake of prostaglandin receptor inhibitors during late gestation but may occur spontaneously. This report describes three live-born infants sharing echocardiographic features of spontaneous intrauterine ductal constriction, closure, or both, although only one had a prenatal diagnosis. Interestingly, in addition to severely hypertrophied right ventricles, all three had hyperechogenic tricuspid valve papillary muscles. Two also had mild ascending aorta dilation. These cases raise mechanistic questions because of intrauterine ductal occlusion, bright papillary muscles, and potential dilated ascending aortas.
Heart transplantation (HTx) implies denervation of afferent neural connections. Reinnervation of low-pressure cardiopulmonary baroreceptors might impact the development and treatment of hypertension, but little is known of its occurrence. The present prospective study investigated possible afferent reinnervation of low-pressure cardiopulmonary baroreceptors during the first year after heart transplantation. MethodsA total of 50 heart transplant recipients (HTxRs) were included and were evaluated 7-12 weeks after transplant surgery, with follow-up 6 and 12 months later. In addition, a reference group of 50 healthy control subjects was examined once. Continuous, non-invasive recordings
Original Clinical Science-General Background. Hypertension after heart transplantation (HTx) is common. We investigated predictors of and mechanisms for hypertension development during the first year after HTx, with particular attention toward immunosuppressive agents, reinnervation processes, and donor/recipient sex. Methods. Heart transplant recipients (HTxRs) were consecutively enrolled 7 to 12 wk after surgery and followed prospectively for 12 mo. Ambulatory blood pressure recordings and autonomic cardiovascular control assessments were performed at baseline and follow-up. Possible predictors of posttransplant hypertension development were investigated in bivariate linear regression analyses followed by multiple regression modeling. Results. A total of 50 HTxRs were included; 47 attended the follow-up appointment at 12 mo. Mean systolic and diastolic blood pressure increased significantly during the observational period (systolic blood pressure from 133 to 139 mm Hg, P = 0.007; diastolic blood pressure from 81 to 84 mm Hg, P = 0.005). The blood pressure increment was almost exclusively confined to HTxRs with a female donor heart, doubling the cases of systolic hypertension (from 6 to 13/14; 46% to 93%, P = 0.031) and diastolic hypertension (from 7 to 14/14; 54% to 100%, P = 0.031) in this subgroup. Autonomic cardiovascular control assessments suggested tonically constricted resistance and capacitance vessels in recipients with female donor hearts. Immunosuppressive agents and reinnervation markers were not associated with hypertension development.Conclusions. Blood pressures increase during the first year after HTx, with female donor sex as a strong predictor of recipient hypertension development. The underlying mechanism seems to be enhanced peripheral vasoconstriction caused by attenuated cardiovascular homeostasis capabilities. Further studies are needed to confirm the results.
Background Left atrial (LA) strain measurements by speckle tracking echocardiography (STE) are predictive markers of cardiovascular morbidity, including atrial fibrillation (AF). LA mechanical dispersion (LA MD) is a new parameter derived from STE. A reduction of LA strain is considered to reflect LA dysfunction, while increased LA MD may reflect LA dyssynchrony. Purpose To assess LA dysfunction and dyssynchrony, as measured by STE, in patients with paroxysmal AF (pAF). Methods A subset of 616 participants in the Akershus Cardiac Examination 1950 Study were divided into three groups: (1) A healthy group (n=179) defined by excluding AF, coronary artery disease, stroke, hypertension, chronic obstructive pulmonary disease, body mass index >30, left ventricular ejection fraction <50%, transmitral E/e' >14 or E/A >2.0, (2) A non-healthy group (n=350) of participants without pAF, but with any of the above conditions, (3) A group with pAF, but in sinus rhythm at examination (n=87). LA reservoir strain (LASr), conduit strain (LAScd) and contractile strain (LASct), as well as LA MD were assessed by STE. MD was defined as the standard deviation (SD) of time from ECG R to peak atrial longitudinal strain (SD-TPS), and corrected by RR-interval (SD-TPS/RR), expressing LA MD as a percentage of the cardiac cycle. Comparisons were made by Mann-Whitney U-test due to non-normal distributions. Results Mean age was 63.5±0.5 years and 46.6% were women. LASr, LAScd and LASct were significantly lower, and LA MD significantly higher in the pAF group compared to the healthy and non-healthy groups (Table; Figure). Conclusion The present study has demonstrated LA dysfunction and dyssynchrony in patients with pAF, which may reflect LA remodeling and increased fibrosis. Figure 1 Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority
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