The relationship between six-minute walked distance and health-related quality of life in patients with chronic heart failure.

Objectives. To assess the relationship between the six-minute walk test (6MWT) and health-related quality of life (HRQL) in patients with chronic heart failure. Methods. Forty-six patients (37 men and 9 women) with chronic heart failure, mean age 68 (SD 9), NYHA II-III and EF 29 (9) % were included. They performed 6MWT and assessed HRQL using two tools, a Swedish version of the 36-item Short Form (SF-36) and the Minnesota Living with Heart Failure Questionnaire (MLHFQ). This was performed repeatedly during a study period of one year. Results. Patients with a walking distance lower than median experienced a lower HRQL than the higher performing half of the cohort, in four dimensions of the SF-36 and the summary of physical and mental components, but not in the dimensions of MLHFQ. Conclusion. Patients with heart failure with a short walking distance assessed their quality of life as inferior in half of the dimensions in the SF-36 but not in the dimensions measured with the MLHFQ. Thus, different aspects of the symptomatology are uncovered using the 6MWT and the different HRQL tools.

Developmental Differences in Left Ventricular Strain in IUGR vs. Control Children the First Three Months of Life.

BACKGROUND: Intrauterine growth restriction (IUGR) may directly affect cardiovascular function in early life. Longitudinal data on left ventricular longitudinal strain (LVLS), a key measure of cardiac function independent of body size, is not available. We hypothesize impaired cardiac function among IUGR newborns and persistence of the impairment until age 3 months. METHOD: This is a prospective cohort study of consecutive pregnancies where IUGR was identified at 18-38 weeks gestational age (GA) with healthy controls randomly selected at 18-20 weeks GA. Echocardiograms were performed at birth and at age 3-4 months, and then compared. RESULTS: At birth, mean (SD) LVLS did not differ between the IUGR group [N = 19; - 15.76 (3.12) %] and controls [N = 35; - 15.53 (3.56) %]. The IUGR group demonstrated no significant change in LVLS at age 3-4 months [- 17.80 (3.82) %], while the control group [- 20.91 (3.31) %] showed a significant increase (P < 0.001). Thus, LVLS was lower in the IUGR group at age 3-4 months (P = 0.003). CONCLUSION: The lack of increase in LVLS may suggest that IUGR has a direct impact on cardiac function as early as during the first months of life. Trial registration Clinical trials.gov Identifier: NCT02583763, registration October 22, 2015. Retrospectively registered September 2014-October 2015, thereafter, registered prospectively.

Moderately trained male football players, compared to sedentary male adults, exhibit anatomical but not functional cardiac remodelling, a cross-sectional study.

BACKGROUND: Elite athletes have been the subject of great interest, but athletes at an intermediate level of physical activity have received less attention in respect to the presence of cardiac enlargement and/or hypertrophy. We hypothesized that playing football, often defined as demanding less endurance components than running or cycling, would still induce remodelling similar to sports with a dominating endurance component. METHODS: 23 male football players, age 25+/- 3.9 yrs. underwent exercise testing, 2D- and 3D- echocardiography and cardiac magnetic resonance (CMR). The results were compared with a control group of engineering students of similar age. The athletes exercised 12 h/week and the control subjects 1 h/week, p < 0.001. RESULTS: The football players achieved a significantly higher maximal load at the exercise test (380 W vs 300 W, p < 0.001) as well as higher calculated maximal oxygen consumption, (49.7 vs 37.4 mL x kg- 1 x min- 1, p < 0.001) compared to the sedentary group. All left ventricular (LV) volumes assessed by 3DEcho and CMR, as well as CMR left atrial (LA) volume were significantly higher in the athletes (3D-LVEDV 200 vs 154 mL, CMR-LVEDV 229 vs 185 mL, CMR-LA volume 100 vs 89 mL, p < 0.001, p = 0.002 and p = 0.009 respectively). LVEF and RVEF, LV strain by CMR or by echo did not differentiate athletes from sedentary participants. Right ventricular (RV) longitudinal strain, LA and right atrial (RA) strain by CMR all showed similar results in the two groups. CONCLUSION: Moderately trained intermediate level football players showed anatomical but not functional cardiac remodelling compared to sedentary males.

Exercise-induced ST depression in an asymptomatic population without coronary artery disease.

Objectives. Exercise electrocardiogram (ExECG) in low risk populations frequently generates false positive ST depression. We aimed to characterize factors that are associated with exercise-induced ST depression in asymptomatic men without coronary artery disease. Design. Cycle ergometer exercise tests from 509 male firefighters without imaging proof of significant coronary artery disease were analysed. Analysed test data included heart rate at rest before exercise, and workload, blood pressure, heart rate, ST depression and ST segment slope at peak exercise. ST depression of >0.1 mV was considered significant (STdep). With a mean follow-up of 6.1 ± 1.7 years, medical records were reviewed for cardiovascular diagnoses, hyperlipidemia and diabetes. Logistic regression analysis was used for risk assessment. Results. In total, 22% had STdep in ≥1 lead. Subjects with STdep were older than those with normal ExECG (p < .001). Downsloping STdep was more common in extremity leads (9%) than in precordial leads (2%). STdep was categorized according to location (precordial/extremity) and slope direction into eight categories. Larger age-adjusted heart rate increase predicted STdep in seven categories (p < .05). Age-adjusted peak heart rate correlated with STdep in five categories, predominantly where the ST slope was positive. Peak blood pressure and exercise capacity were both associated with STdep in few categories. We found no association between STdep and hypertension, hyperlipidemia or diabetes (all p > .05). Conclusions. In asymptomatic men with a physically demanding occupation and no coronary artery disease, both age and heart rate response were associated with ST depression, whereas common cardiovascular risk factors, blood pressure response and exercise capacity were not.

Longitudinal changes in myocardial T1 and T2 relaxation times related to diffuse myocardial fibrosis in aortic stenosis; before and after aortic valve replacement.

BACKGROUND: Diffuse myocardial fibrosis is associated with adverse outcomes, although detection and quantification is challenging. Cardiac MR relaxation times mapping represents a promising imaging biomarker for diffuse myocardial fibrosis. PURPOSE: To investigate whether relaxation times can detect longitudinal changes in myocardial tissue composition associated with diffuse fibrosis in patients with severe aortic stenosis (AS) before and after aortic valve replacement (AVR). STUDY TYPE: Prospective longitudinal study. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL: Fifteen patients with severe AS. FIELD STRENGTH/SEQUENCE: 3T / 3(3)3(3)5-MOLLI, T2 -GraSE, and 3D-QALAS. ASSESSMENT: Patients underwent MR examinations at three timepoints: before AVR, as well as 3 and 12 months after AVR. Data from each patient was analyzed in 16 myocardial segments. STATISTICAL TESTS: The segment-wise T1 and T2 data were analyzed over time after surgery using linear mixed models for repeated measures analysis. RESULTS: The results showed that T1 relaxation times were significantly (P < 0.05) shorter 3 and 12 months postoperative than preoperative and that the T2 relaxation times were significantly (P < 0.05) longer 3 and 12 months postoperative than preoperative for both 3D and 2D mapping methods. No significant changes were seen between 3 and 12 months postoperative for any of the methods (P = 0.06/0.19 for T1 with 3D-QALAS/MOLLI and P = 0.09/0.25 for T2 with 3D-QALAS/GraSE). DATA CONCLUSION: We demonstrated that changes in myocardial relaxation times and thus tissue characteristics can be observed within 3 months after AVR surgery. The significant changes in relaxation times from preoperative examinations to the follow-up may be interpreted as a reduction of interstitial fibrosis in the left ventricular wall. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018.

Body fat in children and adolescents participating in organized sports: Descriptive epidemiological study of 6048 Latvian athletes.

BACKGROUND: Pressure among young athletes to meet body composition goals may lead to poor nutrition and affect growth. AIMS: To examine the proportion of body fat (%BF), measured by bioimpedance analysis, among Latvian children and adolescents participating in organized sports. METHODS: Our study had a nationally representative sample of 6048 young athletes, aged 10-17 years. Their %BF was measured using a multifrequency, 8-pole, bioelectrical impedance leg-to-hand analyzer. RESULTS: About 19.2% (CI 14.4-20.0) of boys and 15.1% (CI 14.0-16.3) of girls had a %BF value below the recommended levels. The %BF in young female athletes participating in aesthetic sports was lower than among their peers participating in other sports. Young male athletes participating in aesthetic sports had lower %BF levels at 10 and 12 years of age, compared with participants in weight-class sports; and lower levels of %BF from age 10-14 years, compared with participants in non-weight-sensitive sports. CONCLUSIONS: Almost every fifth child and adolescent participating in organized sports displayed critically low body fat levels. Body fat needs to be assessed regularly in young athletes, to prevent negative consequences on health.

Exercise echocardiography predicts postoperative left ventricular remodeling in aortic regurgitation.

OBJECTIVE: We aimed to investigate if preoperative left ventricular (LV) function assessed by exercise echocardiography could predict late postoperative LV function in aortic regurgitation (AR) patients and to evaluate how LV long-axis function is affected late after aortic valve surgery. DESIGN: A total of 21 male chronic AR patients, aged 49 ( 12 ) years, accepted for surgery were examined preoperatively, 6 months-, and 4 years postoperatively, at rest and during exercise. Besides conventional echocardiographic parameters, the atrioventricular plane displacement (AVPD) by M-mode and peak systolic velocity (s') in the basal LV by color tissue Doppler were measured. RESULTS: Preoperatively EF rest and EF exercise, were 55( 7 )% and 54( 9 )%, respectively, and ∆EF 0( 8 )%. LV dimensions and volumes indexed to BSA had decreased at the 6-month follow-up and were stable at late follow-up. s'rest, s'exercise, AVPD rest, and AVPD exercise were unchanged at both the postoperative examinations (all P ≥ 0.05). Preoperative EF exercise and AVPD exercise showed inverse correlation to late postoperative indexed LV enddiastolic volume (r = -0.68, p < 0.004 and r = -0.86, P < 0.001) and indexed LV endsystolic volume (r = -0.68, P = 0.004 and r = -0.81, P < 0.001), while there was no correlation to preoperative EF rest and AVPD rest (all r < 0.2). CONCLUSIONS: Preoperative exercise echocardiography can detect AR patients with suboptimal LV remodeling late postoperatively.

Right ventricular function in severe aortic stenosis assessed by echocardiography and MRI.

BACKGROUND: The prevalence of aortic valve stenosis (AS) is increasing due to an ageing population. Despite that right ventricular function has prognostic value for postoperative outcome, the right ventricle (RV) is not extensively studied and often not routinely assessed in AS. Our aim was to explore the relation between severe AS and RV function in a surgical aortic valve replacement (SAVR) cohort, comparing two imaging modalities for RV evaluation. METHODS: Patients with severe AS, underwent cardiovascular magnetic resonance imaging (CMR) and transthoracic echocardiography (TTE) before SAVR. RV dysfunction was defined as one or more of the following: tricuspid annular plane systolic excursion (TAPSE) < 17 mm, RV free wall strain (RVFWS) > -20% by TTE and RV ejection fraction (RVEF) <50% by CMR. RESULTS: Sixteen (33%) patients were found to have RV dysfunction. Patients with RV dysfunction showed significantly lower indexed aortic valve area, left ventricular (LV) ejection fraction as well as RV and LV stroke volumes compared to patients with maintained RV function. All patients with reduced RVEF also had changes in TAPSE or RVFWS and a larger number of patients had a reduced longitudinal RV function despite a normal RVEF. CONCLUSION: In a SAVR cohort one-third of the patients had RV dysfunction, defined by RVEF, TAPSE or RVFW strain. Echocardiography detected subtle changes in RV function before RVEF was reduced. It is likely that the more pronounced the AS, the more frequent the occurrence of RV dysfunction.

Differences in recovery of left and right ventricular function following aortic valve interventions: a longitudinal echocardiographic study in patients undergoing surgical, transapical or transfemoral aortic valve implantation.

OBJECTIVES: To evaluate longitudinal left and right ventricular function (LVF and RVF) after transcatheter aortic valve implantation (TAVI) as compared to surgical aortic valve replacement (SAVR) and LVF and RVF after TAVI by the transfemoral (TF) or transapical (TA) approach. BACKGROUND: Knowledge about differences in recovery of LVF and RVF after TAVI and SAVR is scarce. METHODS: Sixty patients (age 81 ± 7 years, logistic EuroSCORE 16 ± 10%), undergoing TAVI (TF: n = 35 and TA: n = 25), were examined by echocardiography including atrioventricular plane displacement (AVPD) and peak systolic velocities (PSV) by tissue Doppler at basal RV free wall, LV lateral wall and septum preprocedurally, 7 weeks and 6 months postprocedurally. Twenty-seven SAVR patients were matched to 27 TAVI patients by age, gender and LVF. RESULTS: Early postintervention, TAVI patients had improved longitudinal LVF. However, when analyzed separately, only TF, but not TA patients, had improved LV lateral and septal AVPD and PSV (all P ≤ 0.01). All TAVI patients, as well as the TF and TA group had unchanged longitudinal LVF between the early and late follow-ups (all P > 0.05). The SAVR group had higher septal LVF than the matched TAVI group preprocedurally, while postoperatively this difference was diminished. Longitudinal RVF was better in the TF group than in the TA group pre- and postprocedurally. Although the SAVR group had superior longitudinal RVF preoperatively, this was inferior to TAVI postoperatively. CONCLUSIONS: Postprocedural longitudinal LVF and RVF in patients undergoing TF-TAVI, TA-TAVI, or SAVR differ considerably. Preservation of longitudinal RVF after TAVI might influence the selection of aortic valve intervention in the future.

Novel plakophilin2 mutation: three-generation family with arrhythmogenic right ventricular cardiomyopathy.

OBJECTIVES: The autosomal dominant form of arrhythmogenic right ventricular cardiomyopathy (ARVC) has been linked to mutations in desmosomal proteins. A mutation in plakophilin 2 (PKP 2) is a frequent cause for ARVC. We describe a new mutation in the PKP2 gene, the genotype-phenotype variation in this mutation and its clinical consequences. DESIGN: Individuals in a three-generation family were investigated after the sudden cardiac death of a young male. Clinical evaluation, electrocardiography, echocardiography, magnetic resonance imaging, endomyocardial biopsy and genetic testing were performed. RESULTS: A novel heterozygote mutation, a c.368G > A transition, located in exon 3 of the PKP2 gene was found (p.Trp123X). The phenotype was characterized by arrhythmia at an early age in some individuals, with mild abnormalities on imaging. CONCLUSIONS: This new plakophilin mutation demonstrates variable penetrance and phenotypic expression in ARVC, and highlights the need of genetic testing and thorough phenotype examination in ARVC pedigrees.

Transcatheter versus surgical treatment for aortic stenosis: patient selection and early outcome.

OBJECTIVES: To describe short-term clinical and echocardiography outcomes in patients undergoing transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). To explore patient selection criteria for treatment with TAVI. DESIGN: TAVI patients (n = 45) were matched to SAVR patients (n = 45) with respect to age within ± 10 years, sex and systolic left ventricular function. RESULTS: TAVI patients were older, 82 ± 8 versus 78 ± 5 years (p = 0.005) and they had higher logEuroSCORE, 16 ± 11% versus 8 ± 4% (p = 0.001). There were no significant differences in 30 days mortality, stroke and myocardial infarction. TAVI patients received less erythrocyte (53% vs. 78%, p = 0.03) and thrombocyte (7% vs. 27%, p = 0.02) transfusions. Postoperative atrial fibrillation was less common (18% vs. 60%, p = 0.001) in the TAVI group. Paravalvular regurgitation was more common in TAVI patients (87% vs. 0%, p = 0.001) and 27% had access site complications. Aortic transvalvular velocity was 2.3 ± 0.4 m/s versus 2.6 ± 0.5 m/s (p = 0.002) and mean valve pressure gradient was 12 ± 4 mmHg versus 15 ± 5 mmHg (p = 0.01) in the TAVI and SAVR groups, respectively. Twenty-nine (64%) of the TAVI patients had logEuroSCORE = 15%. CONCLUSIONS: Both TAVI and SAVR have good short term clinical outcome with excellent hemodynamic result. In clinical practice, factors other than high logEuroSCORE play an important role in patient selection for TAVI.

Evaluation of right and left ventricular function using speckle tracking echocardiography in patients with arrhythmogenic right ventricular cardiomyopathy and their first degree relatives.

INTRODUCTION AND AIM: The identification of right ventricular abnormalities in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) in early stages is still difficult. The aim of this study was to investigate if longitudinal strain based on speckle tracking can detect subtle right (RV) or left ventricular (LV) dysfunction as an early sign of ARVC. METHODS AND RESULTS: Seventeen male patients, fulfilling Task force criteria for ARVC, 49 (32-70) years old, nineteen male first degree relatives 29 (19-73) y.o. and twenty-two healthy male volunteers 36 (24-66) y.o participated in the study. Twelve-lead and signal-averaged electrocardiograms were recorded. All subjects underwent echocardiography. LV and RV diameters, peak systolic velocity from tissue Doppler and longitudinal strain based on speckle tracking were measured from the basal and mid segments in both ventricles. RV longitudinal strain measurement was successful in first degree relatives and controls (95 resp. 86%) but less feasible in patients (59%). Results were not systematically different between first degree relatives and controls. Using discriminant analysis, we then developed an index based on echocardiographic parameters. All normal controls had an index

Classification and occurrence of an abnormal breathing pattern during cardiopulmonary exercise testing in subjects with persistent symptoms following COVID-19 disease.

Reduced exercise capacity and several limiting symptoms during exercise have been reported following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. From clinical observations, we hypothesized that an abnormal breathing pattern (BrP) during exercise may be common in these patients and related to reduced exercise capacity. We aimed to (a) evaluate a method to classify the BrP as normal/abnormal or borderline in terms of inter-rater agreement; (b) determine the occurrence of an abnormal BrP in patients with post-COVID; and (c) compare characteristics of post-COVID patients with normal and abnormal BrP. In a retrospective, cross-sectional study of patients referred for CPET due to post-COVID April 2020-April 2021, we selected subjects without a history of intensive care and with available medical records. Three raters independently categorized patients' BrP as normal, abnormal, or borderline, using four traditional CPET plots (respiratory exchange ratio, tidal volume over ventilation, ventilatory equivalent for oxygen, and ventilation over time). Out of 20 patients (11 male), 10 were categorized as having a normal, 7 an abnormal, and three a borderline BrP. Inter-rater agreement was good (Fleiss' kappa: 0.66 [0.66-0.67]). Subjects with an abnormal BrP had lower peak ventilation, lower exercise capacity, similar ventilatory efficiency and a similar level of dyspnea at peak exercise, as did subjects with a normal BrP. Patients' BrP was possible to classify with good agreement between observers. A third of patients had an abnormal BrP, associated with lower exercise capacity, which could possibly explain exercise related symptoms in some patients with post-COVID syndrome.

Evaluation of left ventricular diastolic function in patients operated for aortic stenosis.

BACKGROUND: Left ventricular diastolic dysfunction is common in patients with aortic valve stenosis (AS) and reportedly affects prognosis after surgical aortic valve replacement (SAVR). Here we investigated whether and how diastolic function (assessed following the most recent guidelines) was affected by SAVR, and whether preoperative diastolic function affected postoperative outcome. We also examined whether long-term mortality was associated with preoperative NT-proBNP and postoperative heart failure (PHF). METHODS: We performed a prospective observational study of 273 patients with AS who underwent AVR with or without concomitant coronary artery bypass surgery. Of these patients, 247 were eligible for assessment of left ventricular (LV) filling pressure. Preoperatively and at the 6-month postoperative follow-up, we measured N-terminal pro-B type natriuretic peptide (NT-proBNP) in serum and assessed diastolic function with Doppler echocardiography. PHF was diagnosed using prespecified criteria. Multivariable logistic regression was performed to explore variables associated with high LV filling pressure. Cox regression was performed to explore variables associated with mortality, accounting for timeto-event. RESULTS: At the time of surgery, 22% (n = 54) of patients had diastolic dysfunction expressed as high LV filling pressure. Of these 54 patients, 27 (50%) showed postoperative diastolic function improvement. Among the 193 patients with preoperative low LV filling pressure, 24 (12%) showed postoperative diastolic function deterioration. Increased long-term mortality was associated with PHF and high preoperative NT-proBNP, but not with preoperative or postoperative diastolic dysfunction. Cox regression revealed the following independent risk factors for long-term mortality: diabetes, renal dysfunction, preoperative NT-proBNP>960 ng/L, age, and male gender. CONCLUSIONS: Surgery for aortic stenosis improved diastolic function in patients with high LV filling pressure in 50% of the patients. Our results could not confirm the previously suggested role of diastolic dysfunction as a marker for poor long-term survival after SAVR. Our findings showed that both PHF and high preoperative NT-proBNP were associated with long-term mortality.

Echo-guided presentation of the aortic valve minimises contrast exposure in transcatheter valve recipients.

OBJECTIVES: We have developed a method using transthoracic echocardiography in establishing optimal visualization of the aortic root, to reduce the amount of contrast medium used in each patient. BACKGROUND: During transcatheter aortic valve implantation, it is necessary to obtain an optimal fluoroscopic projection for deployment of the valve showing the aortic ostium with the three cusps aligned in the beam direction. This may require repeat aortic root angiograms at this stage of the procedure with a high amount of contrast medium with a risk of detrimental influence on renal function. METHODS: We studied the conventional way and an echo guided way to optimize visualisation of the aortic root. Echocardiography was used initially allowing easier alignment of the image intensifier with the transducer's direction. RESULTS: Contrast volumes, radiation/fluoroscopy exposure times, and postoperative creatinine levels were significantly less in patients having the echo-guided orientation of the optimal fluoroscopic angles compared with patients treated with the conventional approach. CONCLUSION: We present a user-friendly echo-guided method to facilitate fluoroscopy adjustment during transcatheter aortic valve implantation. In our series, the amounts of contrast medium and radiation have been significantly reduced, with a concomitant reduction in detrimental effects on renal function in the early postoperative phase.

Left and right ventricular function in aortic stenosis patients 8 weeks post-transcatheter aortic valve implantation or surgical aortic valve replacement.

AIMS: Knowledge of longitudinal left and right ventricular (LV and RV) function after transcatheter aortic valve implantation (TAVI) is scarce. We hypothesized that the longitudinal systolic biventricular function in aortic stenosis (AS) patients is affected differently by TAVI and surgical aortic valve replacement (SAVR). METHODS AND RESULTS: Thirty-three AS patients (all-TAVI group, age 81 ± 9 years, 18 female), with EuroSCORE 18 ± 9%, were accepted for TAVI. Seventeen of these patients were matched (by gender, age, and LV function) to 17 patients undergoing SAVR. Conventional echocardiographic parameters, systolic atrioventricular plane displacement (AVPD) at standard sites and peak systolic velocity (PSV) by pulsed tissue Doppler at basal RV free wall, LV lateral wall, and septum were studied before and 8 weeks after the procedure. Procedural success was 100%, and 30-day mortality 9%. In all TAVI patients, AVPD(lateral), PSV(lateral), AVPD(septal), and PSV(septal) increased (P< 0.001, 0.003, 0.006 and 0.002). When studying the matched patients postoperatively, both the SAVR and TAVI patients had increased PSV(lateral) and AVPD(lateral) (SAVR: P=0.03 and P=0.04, TAVI: P=0.04 and P=0.01). The PSV(RV) increased in the all-TAVI group (P=0.007), while the AVPD(RV) was unchanged. SAVR patients had decreased AVPD(RV) (P=0.001) and PSV(RV) (P=0.004), while the matched TAVI patients had unchanged RV function parameters. CONCLUSION: An improvement in regional longitudinal LV function in the septal and lateral wall could be seen after TAVI. Among the matched patients, both the TAVI and SAVR patients seemed to improve LV function in the lateral wall. RV systolic function increased in TAVI patients, but was impaired in the matched SAVR group at the 8-week follow-up.

Electrocardiographic amplitudes: a new risk factor for sudden death in hypertrophic cardiomyopathy.

AIMS: Assessment of ECG-features as predictors of sudden death in adults with hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: ECG-amplitude sums were measured in 44 normals, 34 athletes, a hospital-cohort of 87 HCM-patients, and 29 HCM-patients with sudden death or cardiac arrest (HCM-CA). HCM-patients with sudden death or cardiac arrest had substantially higher ECG-amplitudes than the HCM-cohort for limb-lead and 12-lead QRS-amplitude sums, and amplitude-duration products (P = 0.00003-P = 0.000002). Separation of HCM-CA from the HCM-cohort is obtained by limb-lead QRS-amplitude sum >or=7.7 mV (odds ratio 18.8, sensitivity 87%, negative predictive value (NPV) 94%, P < 0.0001), 12-lead amplitude-duration product >or=2.2 mV s (odds ratio 31.0, sensitivity 92%, NPV 97%, P < 0.0001), and limb-lead amplitude-duration product >or=0.70 mV s (odds ratio 31.5, sensitivity 93%, NPV 96%, P < 0.0001). Sensitivity in HCM-patients <40 years is 90, 100, and 100% for those ECG-variables, respectively. Qualitative analysis showed correlation with cardiac arrest for pathological T-wave-inversion (P = 0.0003), ST-depression (P = 0.0010), and dominant S-wave in V(4) (P = 0.0048). A risk score is proposed; a score >or=6 gives a sensitivity of 85% but a higher positive predictive value than above measures. Optimal separation between HCM-CA <40 years and athletes is obtained by a risk score >or=6 (odds ratio 345, sensitivity 85%, specificity 100%, P < 0.0001). CONCLUSION: Twelve-lead ECG is a powerful instrument for risk-stratification in HCM.

Alteration of PHYA expression change circadian rhythms and timing of bud set in Populus.

In many temperate woody species, dormancy is induced by short photoperiods. Earlier studies have shown that the photoreceptor phytochrome A (phyA) promotes growth. Specifically, Populus plants that over-express the oat PHYA gene (oatPHYAox) show daylength-independent growth and do not become dormant. However, we show that oatPHYAox plants could be induced to set bud and become cold hardy by exposure to a shorter, non-24 h diurnal cycle that significantly alters the relative position between endogenous rhythms and perceived light/dark cycles. Furthermore, we describe studies in which the expression of endogenous Populus tremula x P. tremuloides PHYTOCHROME A (PttPHYA) was reduced in Populus trees by antisense inhibition. The antisense plants showed altered photoperiodic requirements, resulting in earlier growth cessation and bud formation in response to daylength shortening, an effect that was explained by an altered innate period that leads to phase changes of clock-associated genes such as PttCO2. Moreover, gene expression studies following far-red light pulses show a phyA-mediated repression of PttLHY1 and an induction of PttFKF1 and PttFT. We conclude that the level of PttPHYA expression strongly influences seasonally regulated growth in Populus and is central to co-ordination between internal clock-regulated rhythms and external light/dark cycles through its dual effect on the pace of clock rhythms and in light signaling.

[Pre-duty medical assessment in fire-fighters requires modernization - relevance of exercise ECG is questioned]. / Oklar nytta av upprepade arbets-EKG hos brandmän.

Medical assessment of Swedish smoke diving firefighters includes cardiac evaluation by maximal exercise testing with ECG recording. The exercise ECG procedure for firefighters was introduced in 1986, and remains consistent in the recently updated guidelines from 2019.  Exercise ECG is a non-invasive and easily available method for detection of chronic coronary syndromes, but due to the declining population risk in high-income countries, its ability to accurately detect disease has decreased. Thus, the clinical relevance of exercise ECG in firefighters is questioned and the pre-duty medical assessment requires modernization.