Elevated sympathetic-mediated vasoconstriction at rest but intact functional sympatholysis during exercise in heart failure with reduced ejection fraction.

Patients with heart failure with reduced ejection fraction (HFrEF) have exaggerated sympathoexcitation and impaired peripheral vascular conductance. Evidence demonstrating consequent impaired functional sympatholysis is limited in HFrEF. This study aimed to determine the magnitude of reduced limb vascular conductance during sympathoexcitation and whether functional sympatholysis would abolish such reductions in HFrEF. Twenty patients with HFrEF and 22 age-matched controls performed the cold pressor test (CPT) [left foot 2-min in -0.5 (1)°C water] alone and with right handgrip exercise (EX + CPT). Right forearm vascular conductance (FVC), forearm blood flow (FBF), and mean arterial pressure (MAP) were measured. Patients with HFrEF had greater decreases in %ΔFVC and %ΔFBF during CPT (both P < 0.0001) but not EX + CPT (P = 0.449, P = 0.199) compared with controls, respectively. %ΔFVC and %ΔFBF decreased from CPT to EX + CPT in patients with HFrEF (both P < 0.0001) and controls (P = 0.018, P = 0.015), respectively. MAP increased during CPT and EX + CPT in both groups (all P < 0.0001). MAP was greater in controls than in patients with HFrEF during EX + CPT (P = 0.025) but not CPT (P = 0.209). In conclusion, acute sympathoexcitation caused exaggerated peripheral vasoconstriction and reduced peripheral blood flow in patients with HFrEF. Handgrip exercise abolished sympathoexcitatory-mediated peripheral vasoconstriction and normalized peripheral blood flow in patients with HFrEF. These novel data reveal intact functional sympatholysis in the upper limb and suggest that exercise-mediated, local control of blood flow is preserved when cardiac limitations that are cardinal to HFrEF are evaded with dynamic handgrip exercise.NEW & NOTEWORTHY Patients with HFrEF demonstrate impaired peripheral blood flow regulation, evidenced by heightened peripheral vasoconstriction that reduces limb blood flow in response to physiological sympathoexcitation (cold pressor test). Despite evidence of exaggerated sympathetic vasoconstriction, patients with HFrEF demonstrate a normal hyperemic response to moderate-intensity handgrip exercise. Most importantly, acute, simultaneous handgrip exercise restores normal limb vasomotor control and vascular conductance during acute sympathoexcitation (cold pressor test), suggesting intact functional sympatholysis in patients with HFrEF.

Muscle metaboreflex control of left ventricular systolic function in heart failure with reduced ejection fraction.

Heart failure with reduced ejection fraction (HFrEF) exhibits exaggerated sympathoexcitation and altered cardiac and vascular responses to muscle metaboreflex activation (MMA). However, left ventricular (LV) responses to MMA are not well studied in patients with HFrEF. The purpose of this study was to examine LV function during MMA using cardiac magnetic resonance imaging (MRI) in patients with HFrEF. Thirteen patients with HFrEF and 18 healthy age-matched controls underwent cardiac MRI during rest and MMA. MMA protocol included 6 min of isometric handgrip exercise followed by 6-min of brachial postexercise circulatory occlusion. LV stroke volume index (SVi), end-systolic volume index (ESVi), end-diastolic volume index (EDVi), and global longitudinal strain (GLS) were measured by two- and four-chamber cine images. Volumes were indexed to body surface area. Heart rate (via ECG) and brachial mean arterial pressure (MAP) were recorded. Cardiac output and total peripheral resistance (TPR) were calculated. SVi decreased during MMA in HFrEF (P = 0.037) but not in controls (P = 0.392). ESVi (P = 0.007) and heart rate (P < 0.001) increased during MMA in HFrEF but not controls (P ≥ 0.170). TPR (P = 0.021) and MAP (P < 0.001) increased during MMA in both groups. Cardiac output (P = 0.946), EDVi (P = 0.177), and GLS (P = 0.619) were maintained from rest to MMA in both groups. Despite similarly maintained cardiac output, LV strain, and increased TPR in HFrEF and control groups, SVi decreased, and heart rate increased during MMA in patients with HFrEF. These findings suggest an impaired contractility reserve in response to increased TPR during MMA in HFrEF.NEW & NOTEWORTHY Stroke volume decreases and end-systolic volume increases during muscle metaboreflex activation in patients with heart failure with reduced ejection fraction (HFrEF), suggesting impaired contractile reserve during muscle metaboreflex activation in patients with HFrEF. Total peripheral resistance increases similarly during muscle metaboreflex activation in patients with HFrEF compared to controls, indicating normal levels of peripheral vasoconstriction during muscle metaboreflex activation in patients with HFrEF.

Heart Failure after Laboratory Confirmed Influenza Infection (FLU-HF).

Background: Influenza has been shown to exacerbate heart failure (HF). Importantly, no study to date has examined the relationship between HF hospitalizations (HFH) with laboratory confirmed influenza infections. This study evaluated the association between laboratory confirmed influenza infection and HFH in the two largest hospitals in Saskatchewan, Canada. Methods: We used a retrospective self-controlled case series design to evaluate the association between laboratory-confirmed influenza infection and HFH. We compared the incidence ratio for HFH during the influenza risk interval with the control interval. We defined the influenza risk interval as the seven days after a laboratory confirmed influenza result and the control interval as one year before and after the risk interval. Results: We identified 114 HFH that occurred within one year before and after a positive test result for influenza between April 1, 2010, and April 30, 2018. Of these, 28 (28 admissions per week) occurred during the risk interval and 86 (0.853 admissions per week) occurred during the control interval. The incidence ratio of a HFH during the risk interval as compared with the control interval was 33.53 (95% confidence interval [CI], 21.89 to 51.36). A decline in incidence was observed after day seven; between days 8 to 14 and 14 to 28 incidence ratios was 0.91 (95% CI, 0.13 to 6.52) and 0.91 (95% CI, 0.22 to 3.68) respectively. Conclusion: We have observed a significant association between acute influenza infection and HFH. However, further research with a larger sample size and involving a multicenter setting is warranted. Highlights: Influenza may contribute and exacerbate heart failure events especially during annual influenza season.Early identification of influenza among patients with heart failure, could lead to earlier treatment with antiviral medication, reduce unnecessary antibiotic use, and tail off the morbidity and mortality.In this study, despite our efficient study design, our sample size was limited to only the two largest hospitals in the province, possibly excluding a significant population in remote areas.

Trends in Patient Characteristic, Cost, and Mortality Among Mechanically Ventilated Adult Patients With Congenital Heart Disease in the United States.

BACKGROUND: There is an increasing number of adults with congenital heart disease (ACHD), but critically ill patients with ACHD remain understudied. The objective of this study was to evaluate patient characteristics and trends in mortality of mechanically ventilated patients with ACHD. METHODS: We evaluated ACHD with an ICD-9 procedure code for mechanical ventilation using the National Inpatient Sample (NIS), a public all-payer inpatient United States database, from 2005 to 2014. Primary and secondary outcomes were evaluated using multivariable logistic regression. RESULTS: There were 10,962 of 77,334,704 discharges, representing 52,876 (0.6%) hospitalizations that were for patients with ACHD who required mechanical ventilation (MV). Mean age was 59 years (interquartile range: 45-71); 45.3% were female patients. The number of patients with ACHD requiring MV increased over the years (2342 to 7775, P < 0.001). Age and comorbidities of this cohort also increased (55 to 59, P < 0.001; 1 to 2, P < 0.001). Case-fatality ratio remained stable over the years (0.254 to 0.259, P = 0.42). Median cost of hospital stay was USD $49,583 and remained stable over the study period (P = 0.42), whereas total cost increased from $115 million to $564 million (P < 0.001). CONCLUSIONS: The number of mechanically ventilated ACHD has increased over the years. Remarkably, despite an increase in the age and comorbidity burden in this cohort, case-fatality ratio of these patients and the cost per patient remained stable. Nonetheless, there is a growing need for health care resources in the management of this cohort of patients. Further studies will need to be conducted to evaluate the underlying physiological impact and prognosis of MV in specific subsets of ACHD.

INTRODUCTION: Il existe un nombre croissant d'adultes atteints d'une cardiopathie congénitale (CC), mais peu d'études portent sur les patients gravement atteints d'une CC. L'objectif de la présente étude était l'évaluation des caractéristiques des patients et des tendances de la mortalité des patients atteints d'une CC sous ventilation mécanique. MÉTHODES: Nous avons évalué les patients atteints d'une CC sous ventilation mécanique (VM, code ICD-9) à l'aide de l'échantillon national des patients hospitalisés (NIS, National Inpatient Sample), une base de données sur les patients hospitalisés des États-Unis accessible au public, de 2005 à 2014. Nous avons évalué les critères de jugement principal et secondaire à l'aide de la régression logistique multivariée. RÉSULTATS: Les 10 962 sorties d'hôpital sur 77 334 704, soit 52 876 (0,6 %) hospitalisations, concernaient des patients atteints d'une CC qui avaient nécessité une VM. L'âge moyen était de 59 ans (écart interquartile : 45-71); 45,3 % étaient des femmes. Le nombre de patients atteints d'une CC qui avaient nécessité une VM augmentait au fil des années (de 2 342 à 7 775, P < 0,001). L'âge et les comorbidités de cette cohorte augmentaient aussi (de 55 à 59, P < 0,001; de 1 à 2, P < 0,001). Le taux de létalité restait stable au fil des années (de 0,254 à 0,259, P = 0,42). Le coût médian des séjours à l'hôpital était de 49 583 $ US et restait stable au cours de la période de l'étude (P = 0,42), alors que le coût total passait de 115 M$ à 564 M$ (P < 0,001). CONCLUSIONS: Le nombre de patients atteints d'une CC sous VM a augmenté au fil des années. Étonnamment, en dépit d'une augmentation de l'âge et du fardeau des comorbidités dans cette cohorte, le taux de létalité de ces patients et le coût par patient demeurait stable. Néanmoins, il existe un urgent besoin de ressources de soins de santé pour la prise en charge de cette cohorte de patients. Il sera nécessaire de mener d'autres études pour évaluer les effets physiologiques sous-jacents et le pronostic des patients sous VM dans des sous-ensembles spécifiques de CC.

Loeys-Dietz syndrome and isolated severe ostial left main coronary stenosis presenting as ventricular fibrillation arrest and biventricular takotsubo syndrome in a 25-year-old patient.

We present the case of a previously healthy 25-year-old woman who presented with an out-of-hospital ventricular fibrillation arrest. Postresuscitation ECG did not show any evidence of ST segment elevation. Echocardiogram showed regional wall abnormalities in keeping with takotsubo syndrome (TTS). Urgent coronary angiogram to rule out malignant congenital coronary artery anomaly revealed an isolated severe ostial left main coronary artery (LMCA) stenosis, a rare disease, approximately 0.2% in previous case series. The LMCA was aneurysmal. Genetic studies revealed a novel frameshift pathogenic variant in the transforming growth factor B two ligand gene (TGFB2) gene, suggestive of Loeys-Dietz syndrome (LDS) type 4, an aggressive vascular disease. Ostial LMCA stenosis has not been previously reported in LDS, and we outline the management of this unique disease combination. We also reflect on its presentation as TTS and infer that TTS and acute coronary syndromes are not mutually exclusive.

Reducing Unnecessary Noninvasive Testing for Inpatients With Unstable Angina: The RUNIT Protocol.

BACKGROUND: Routine inpatient transthoracic echocardiography (TTE) for patients with unstable angina is common, but it anecdotally adds little value to clinical care. A practice audit at our academic hospital demonstrated that 61.5% of patients with troponin-negative chest pain (TNCP) had normal left ventriculography (LVG) during coronary angiography and normal TTE on the same admission (duplicate testing). METHODS: We developed the Reducing Non-Invasive Testing (RUNIT) protocol, a clinical algorithm applied by clinical nurses to patient with TNCP. We performed a prospective assessment of rate of duplicate testing before and after intervention. If patients met certain simple clinical criteria, their TTE was cancelled (RUNIT positive). Patients then proceeded to have either coronary angiography with LVG or noninvasive risk stratification. We aimed to reduce duplicate testing by 25% over a 1-year period. Balancing measures included pathology on ordered TTEs, 30-day readmission, length of stay, and number of LVG. RESULTS: Among 254 patients admitted with TNCP over 12 months, we reduced duplicate testing from 61.5% (before intervention) to 34% (P = 0.001). There was no clinical difference in 30-day readmission (0.9% vs 0.7%), and length of stay was significantly shorter in RUNIT positive (3.48 vs 4.16 days, P = 0.02). The majority of duplicate TTEs did not reveal any management-informing pathology. RUNIT-positive patients underwent more LVG than RUNIT-negative patients (78.3% vs 62.8%, P = 0.008). CONCLUSION: We achieved a sustained reduction in reflexive TTE ordering in patients with TNCP, and we discuss the potential of nursing-led interventions to address other areas of low value care in cardiology.

CONTEXTE: La réalisation systématique d'une échocardiographie transthoracique (ETT) chez les patients hospitalisés pour angine instable est une pratique courante, qui n'apporte toutefois qu'une valeur anecdotique aux soins cliniques. Un audit des pratiques en vigueur dans l'hôpital universitaire auquel nous sommes rattachés a révélé que 61,5 % des patients ayant une douleur thoracique sans élévation de la troponine (DTST) présentaient une ventriculographie gauche (VGG) normale à la coronarographie et une ETT normale lors de la même admission (tests effectués en double). MÉTHODOLOGIE: Nous avons mis au point le protocole RUNIT ( R ed u cing N on- I nvasive T esting, réduction des tests non invasifs), un algorithme clinique appliqué par le personnel infirmier clinicien aux patients présentant une DTST. Nous avons ensuite mené une évaluation prospective du taux de réalisation de tests en double avant et après l'intervention. Si les patients répondaient à certains critères cliniques simples, l'ETT n'était pas effectuée (score RUNIT positif). Les patients ont par la suite été soumis soit à une coronarographie et à une VGG, soit à une stratification du risque associé aux méthodes non invasives. Notre objectif était de réduire de 25 % la réalisation de tests en double sur une période de 1 an. Les mesures de compensation comprenaient une évaluation pathologique des résultats des ETT demandées, la réadmission à 30 jours, la durée de l'hospitalisation et le nombre de VGG. Résultats : Parmi les 254 patients admis en raison d'une DTST sur une période de 12 mois, nous avons réduit la réalisation de tests en double de 61,5 % (avant l'intervention) à 34 % (p = 0,001). Il n'y avait pas de différence clinique quant au taux de réadmission à 30 jours (0,9 % vs 0,7 %), et l'hospitalisation a été beaucoup plus courte chez les patients ayant obtenu un score RUNIT positif (3,48 vs 4,16 jours, P = 0,02). La majorité des ETT réalisées en double n'ont mis au jour aucune caractéristique pathologique permettant d'éclairer la prise en charge. Les patients qui ont obtenu un score RUNIT positif ont par ailleurs subi un plus grand nombre de VGG que ceux qui ont obtenu un score négatif (78,3 % vs 62,8 %, p = 0,008). CONCLUSION: Nous avons réussi à réduire de manière soutenue la réalisation systématique d'ETT chez les patients présentant une DTST, et nous traitons de la possibilité de mettre en place des protocoles à appliquer par le personnel infirmier afin de réduire l'exécution d'autres interventions n'apportant que peu de valeur aux soins en cardiologie.

Frequency and Consequences of Influenza Vaccination in Adults With Congenital Heart Disease.

Immunization against influenza is a critical, but perhaps underappreciated prevention of morbidity and mortality in the cardiac population. The purpose of the present study is to examine influenza vaccination rates in adults with congenital heart disease (ACHD). A secondary purpose is to explore whether there is an association between demographic, medical, and behavioral variables and receipt of the influenza vaccination. Of the 183 consecutive ACHD patients who were contacted, 123 responded to our telephone survey. Mean age was 38.4 ± 14.7, with the most common type of lesion complexity being moderate (65.3%), followed by simple (21.0%) and severe (13.7%). Overall, 53 respondents reported undergoing influenza vaccination in the previous season. Fifty-two percent of all subjects claimed they were notified of the benefits of vaccination by their physician. Univariate analysis revealed that older age (p = 0.006), female gender (p = 0.027), perceived susceptibility to influenza illness (p <0.001), perceived severity of the influenza illness (p <0.001), perceived benefits of the influenza vaccination (p <0.001), side effects from previous immunization (p = 0.006), and physician recommendation (p = 0.008) were predictors of receipt of influenza vaccination. On multivariate analyses, however, only side effects from previous immunization was a predictor (odds ratio = 0.34 [95% confidence interval 0.13 to 0.91]), whereas physician recommendation was numerically, but not statistically, significant (odds ratio 2.01 [95% confidence interval 0.85 to 4.78]). Our study demonstrated that less than 50% of ACHD population receives influenza vaccination. We believe educating both the patients about the side effects of vaccination and the physicians about their role in counseling ACHD patients will increase the vaccination rates in this high-risk population.