Telemedicine in Swedish primary health care - a web-based survey exploring patient satisfaction.

BACKGROUND: Direct-to-consumer telemedicine (TM), with patients having access to a physician via video or text chat, has gradually been introduced into Swedish primary care during the last two decades. Earlier studies have concluded that patients were generally satisfied with TM and the satisfaction rate was consistently above 80% and comparable with in-person visits. Despite the number of studies looking at user experience, studies assessing what factors influence patient satisfaction are lacking. To further develop digital care, it is important to explore the patients' opinions of this relatively new phenomenon. The primary aim of this study was to explore patient opinions regarding satisfaction with TM-provided care, based on different age groups, sex, symptoms, and which type of health care professional they were assessed by. METHODS: The study was a quantitative web survey performed in 2020-2021 in which 688 patients using a TM provider in Southern Sweden responded. The results were analysed using Chi-2 test with the main outputs; satisfaction level and percentage that would use TM for similar symptoms in the future. RESULTS: The results from the survey population show that patients that were assessed by a doctor were more likely to intend to use TM in the future and were more satisfied with the visit than patients assessed by a nurse. Our results also show that patients older than 70 years of age were less likely to use TM again compared to the total population. CONCLUSION: This study shows that patient satisfaction with TM varied depending on the patient's age. The older patients were less satisfied than their younger equivalents. For patient satisfaction to be high, it was also crucial which health care provider the patient had been assessed by. The patients were more satisfied when assessed by a doctor than by a nurse. In addition, the study shows that patient satisfaction with TM was generally comparable to traditional care.

Evolution of P-wave indices during long-term follow-up as markers of atrial substrate progression in arrhythmogenic right ventricular cardiomyopathy.

AIMS: Patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) have increased prevalence of atrial arrhythmias indicating atrial involvement in the disease. We aimed to assess the long-term evolution of P-wave indices as electrocardiographic (ECG) markers of atrial substrate during ARVC progression. METHODS AND RESULTS: We included 100 patients with a definite ARVC diagnosis according to 2010 Task Force criteria [34% females, median age 41 (inter-quartile range 30-55) years]. All available sinus rhythm ECGs (n = 1504) were extracted from the regional electronic ECG databases and automatically processed using Glasgow algorithm. P-wave duration, P-wave area, P-wave frontal axis, and prevalence of abnormal P terminal force in lead V1 (aPTF-V1) were assessed and compared at ARVC diagnosis, 10 years before and up to 15 years after diagnosis.Prior to ARVC diagnosis, none of the P-wave indices differed significantly from the data at ARVC diagnosis. After ascertainment of ARVC diagnosis, P-wave area in lead V1 decreased from -1 to -30 µV ms at 5 years (P = 0.002). P-wave area in lead V2 decreased from 82 µV ms at ARVC diagnosis to 42 µV ms 10 years after ARVC diagnosis (P = 0.006). The prevalence of aPTF-V1 increased from 5% at ARVC diagnosis to 18% by the 15th year of follow-up (P = 0.004). P-wave duration and frontal axis did not change during disease progression. CONCLUSION: Initial ARVC progression was associated with P-wave flattening in right precordial leads and in later disease stages an increased prevalence of aPTF-V1 was seen.

Right ventricular stroke work index by echocardiography in adult patients with pulmonary arterial hypertension.

BACKGROUND: In adult patients with pulmonary arterial hypertension (PAH), right ventricular (RV) failure may worsen rapidly, resulting in a poor prognosis. In this population, non-invasive assessment of RV function is challenging. RV stroke work index (RVSWI) measured by right heart catheterization (RHC) represents a promising index for RV function. The aim of the present study was to comprehensively evaluate non-invasive measures to calculate RVSWI derived by echocardiography (RVSWIECHO) using RHC (RVSWIRHC) as a reference in adult PAH patients. METHODS: Retrospectively, 54 consecutive treatment naïve patients with PAH (65 ± 13 years, 36 women) were analyzed. Echocardiography and RHC were performed within a median of 1 day [IQR 0-1 days]. RVSWIRHC was calculated as: (mean pulmonary arterial pressure (mPAP)-mean right atrial pressure (mRAP)) x stroke volume index (SVI)RHC. Four methods for RVSWIECHO were evaluated: RVSWIECHO-1 = Tricuspid regurgitant maximum pressure gradient (TRmaxPG) x SVIECHO, RVSWIECHO-2 = (TRmaxPG-mRAPECHO) x SVIECHO, RVSWIECHO-3 = TR mean gradient (TRmeanPG) x SVIECHO and RVSWIECHO-4 = (TRmeanPG-mRAPECHO) x SVIECHO. Estimation of mRAPECHO was derived from inferior vena cava diameter. RESULTS: RVSWIRHC was 1132 ± 352 mmHg*mL*m-2. In comparison with RVSWIRHC in absolute values, RVSWIECHO-1 and RVSWIECHO-2 was significantly higher (p < 0.001), whereas RVSWIECHO-4 was lower (p < 0.001). No difference was shown for RVSWIECHO-3 (p = 0.304). The strongest correlation, with RVSWIRHC, was demonstrated for RVSWIECHO-2 (r = 0.78, p < 0.001) and RVSWIECHO-1 ( r = 0.75, p < 0.001). RVSWIECHO-3 and RVSWIECHO-4 had moderate correlation (r = 0.66 and r = 0.69, p < 0.001 for all). A good agreement (ICC) was demonstrated for RVSWIECHO-3 (ICC = 0.80, 95% CI 0.64-0.88, p < 0.001), a moderate for RVSWIECHO-4 (ICC = 0.73, 95% CI 0.27-0.87, p < 0.001) and RVSWIECHO-2 (ICC = 0.55, 95% CI - 0.21-0.83, p < 0.001). A poor ICC was demonstrated for RVSWIECHO-1 (ICC = 0.45, 95% CI - 0.18-0.77, p < 0.001). Agreement of absolute values for RVSWIECHO-1 was - 772 ± 385 (- 50 ± 20%) mmHg*mL*m-2, RVSWIECHO-2 - 600 ± 339 (-41 ± 20%) mmHg*mL*m-2, RVSWIECHO-3 42 ± 286 (5 ± 25%) mmHg*mL*m-2 and for RVSWIECHO-4 214 ± 273 (23 ± 27%) mmHg*mL*m-2. CONCLUSION: The correlation with RVSWIRHC was moderate to strong for all echocardiographic measures, whereas only RVSWIECHO-3 displayed high concordance of absolute values. The results, however, suggest that RVSWIECHO-1 or RVSWIECHO-3 could be the preferable echocardiographic methods. Prospective studies are warranted to evaluate the clinical utility of such measures in relation to treatment response, risk stratification and prognosis in patients with PAH.

Right ventricular function parameters in pulmonary hypertension: echocardiography vs. cardiac magnetic resonance.

BACKGROUND: Right ventricular (RV) function is a major determinant of outcome in patients with pulmonary hypertension. Cardiac magnetic resonance (CMR) is gold standard to assess RV ejection fraction (RVEFCMR), however this is a crude measure. New CMR measures of RV function beyond RVEFCMR have emerged, such as RV lateral atrio-ventricular plane displacement (AVPDlat), maximum emptying velocity (S'CMR), RV fractional area change (FACCMR) and feature tracking of the RV free wall (FWSCMR). However, it is not fully elucidated if these CMR measures are in parity with the equivalent echocardiography-derived measurements: tricuspid annular plane systolic excursion (TAPSE), S'-wave velocity (S'echo), RV fractional area change (FACecho) and RV free wall strain (FWSecho). The aim of this study was to compare regional RV function parameters derived from CMR to their echocardiographic equivalents in patients with pulmonary hypertension and to RVEFCMR. METHODS: Fifty-five patients (37 women, 62 ± 15 years) evaluated for pulmonary hypertension underwent CMR and echocardiography. AVPDlat, S'CMR, FACCMR and FWSCMR from cine 4-chamber views were compared to corresponding echocardiographic measures and to RVEFCMR delineated in cine short-axis stack. RESULTS: A strong correlation was demonstrated for FAC whereas the remaining measurements showed moderate correlation. The absolute bias for S' was 2.4 ± 3.0 cm/s (relative bias 24.1 ± 28.3%), TAPSE/AVPDlat 5.5 ± 4.6 mm (33.2 ± 25.2%), FWS 4.4 ± 5.8% (20.2 ± 37.5%) and for FAC 5.1 ± 8.4% (18.5 ± 32.5%). In correlation to RVEFCMR, FACCMR and FWSecho correlated strongly, FACecho, AVPDlat, FWSCMR and TAPSE moderately, whereas S' had only a weak correlation. CONCLUSION: This study has demonstrated a moderate to strong correlation of regional CMR measurements to corresponding echocardiographic measures. However, biases and to some extent wide limits of agreement, exist between the modalities. Consequently, the equivalent measures are not interchangeable at least in patients with pulmonary hypertension. The echocardiographic parameter that showed best correlation with RVEFCMR was FWSecho. At present, FACecho and FWSecho as well as RVEFCMR are the preferred methods to assess and follow up RV function in patients with pulmonary hypertension. Future investigations of the CMR right ventricular measures, beyond RVEF, are warranted.

Effects of oxygen therapy on wall-motion score index in patients with ST elevation myocardial infarction-the randomized SOCCER trial.

BACKGROUND: Although oxygen (O2 ) is routinely used in patients with acute myocardial infarction (AMI), it may have negative effects. In this substudy of the SOCCER trial, we aimed to evaluate the effects of O2 -treatment on myocardial function in patients with ST elevation myocardial infarction (STEMI). METHODS: Normoxic (≥94%) STEMI patients were randomized in the ambulance to either supplemental O2 or room air until the end of the percutaneous coronary intervention (PCI). The patients underwent echocardiography on day 2-3 after the PCI and once again after 6 months. The study endpoints were wall-motion score index (WMSI) and left ventricular ejection fraction (LVEF). RESULTS: Forty-six patients in the O2 group and 41 in the air group were included in the analysis. The index echocardiography showed no significant differences between the groups in WMSI (1.32±0.27 for O2 group vs 1.28±0.28 for air group) or LVEF (47.0±8.5% vs 49.2±8.1%). Nor were there differences at 6 months in WMSI (1.16±0.25 vs 1.14±0.24) or LVEF (53.5±5.8% vs 53.5±6.9%). CONCLUSION: The present findings indicate no harm or benefit of supplemental O2 on myocardial function in STEMI patients. Our results support that it is safe to withhold supplemental O2 in normoxic STEMI patients.

Determinants of left atrial reverse remodeling after valve surgery for degenerative mitral regurgitation.

BACKGROUND AND AIM OF THE STUDY: Left atrial (LA) enlargement is a pathophysiological response to volume overload resulting from chronic mitral regurgitation (MR), is known as LA remodeling, and has been shown previously to be associated with cardioembolic events. Following mitral valve surgery (MVS), the left atrium may undergo reverse remodeling characterized by LA volume reduction. The study aim was to evaluate the incidence and determinants of postoperative left atrial reverse remodeling (LARR) following MVS. METHODS: The postoperative left atrial volume index (LAVi) was determined echocardiographically in patients with degenerative chronic MR undergoing isolated MVS (n = 110), using three different algorithms, and compared to the preoperative values. LARR was defined as a reduction in LAVi > or = 15%. RESULTS: The postoperative mean LA diameter (p < 0.001), LA area (p < 0.001), and LAVi (p < 0.001) were each decreased significantly. LARR was observed in 84 patients (76%), with a mean postoperative LAVi reduction of 29 +/- 26%. Younger patients (aged < 60 years) demonstrated a significantly greater degree of LARR (p = 0.022). A high preoperative LAVi was found to be an independent predictor of impaired reverse remodeling (OR 0.98, p = 0.002, 95% CI 0.97-0.99). CONCLUSION: Following MVS, LARR was observed in the majority of patients studied, including those with a high preoperative LAVi, but to a lesser extent. Patients with preoperative LA enlargement should be closely monitored, with a low threshold for surgical admittance, as the potential for postoperative LARR decreases with increasing preoperative LAVi.

Left atrial reverse remodeling following valve surgery for chronic degenerative mitral regurgitation in patients with preoperative sinus rhythm: effects on long-term outcome.

BACKGROUND AND AIM OF STUDY: Chronic degenerative mitral regurgitation (MR) with left atrial (LA) enlargement is predictive of adverse cardiovascular events including stroke, atrial fibrillation (AF), and impaired survival. Mitral valve surgery (MVS) initiates left atrial reverse remodeling (LARR) characterized by LA volume reduction and improved function. The aim of this study was to evaluate the effects of LARR on clinical outcome in patients with and without LARR following MVS. METHODS: A retrospective study was conducted of 137 consecutive patients in sinus rhythm with degenerative severe MR undergoing isolated MVS. The left atrial volume index (LAVi) was assessed by studying pre- and postoperative echocardiograms; LARR was defined as a reduction in LAVi ≥ 15%. Clinical outcome was evaluated in relation to the absolute and relative reduction in LAVi, and the presence or absence of postoperative LARR. RESULTS: The incidence of postoperative LARR was 74% (n = 101). The overall 90-day survival was 100%. Freedom from complications and cardiac events 10 years after surgery for patients with LARR versus those without was: 92 ± 4% versus 66 ± 13% (p = 0.088) for mortality; 72 ± 1% versus 51 ± 18% (p = 0.131) for new onset of chronic AF; 72 ± 1% versus 81 ± 6% (p = 0.477) for cerebral thromboembolism; and 50 ± 10% versus 49 ± 11% (p = 0.744) for major cardiac adverse events. CONCLUSIONS: Preoperative LA enlargement due to severe degenerative MR in patients with sinus rhythm demonstrates a high potential for postoperative reverse remodeling following MVS. The absence of postoperative LARR was not associated with an increase in the risk of postoperative mortality or adverse clinical events.

Prognostic value of pulmonary hypertension in patients undergoing surgery for degenerative mitral valve disease with leaflet prolapse.

BACKGROUND AND AIM OF THE STUDY: The aim of this study was to evaluate the impact of pulmonary hypertension (PH) on early and late outcomes following surgery in patients with degenerative mitral regurgitation. METHODS: The study included 270 patients who had undergone isolated mitral valve surgery (MVS) for leaflet prolapse during 1998 to 2010. Pulmonary artery systolic pressure (PASP) was measured with Doppler echocardiography pre- and postoperatively. The impact of PH (PASP > 50 mmHg) on mortality and the potential for postoperative resolution of preoperatively elevated PASP was retrospectively analyzed. RESULTS: The incidence of PH was 27% (n = 74/270). Postoperative normalization, or reduction of preoperative PASP, was demonstrated in 87% of the patients with PH at a median of two months (interquartile range 1 to 19). Absent improvement or a postoperative increase in PASP was independently predicted by age (OR 1.08, 95% CI 1.02-1.14, p = 0.010). Preoperative PH resulted in a fourfold higher risk of postoperative mortality (HR 4.3, 95% CI 1.1-17.4, p = 0.039) during the first three years of follow-up. CONCLUSIONS: PH is an independent predictor of mortality during the initial three years following MVS. The majority of patients with PH demonstrated a reduction of preoperatively elevated PASP following surgery and the increased risk of mortality gradually decreased after three years. Our findings support early admission for mitral valve surgery before the occurrence of PH.

Impact of bridging with left ventricular assist device on right ventricular function following heart transplantation.

AIMS: Patients awaiting orthotopic heart transplantation (OHT) can be bridged utilizing a left ventricular assist device (LVAD) that reduces left ventricular filling pressures, decreases pulmonary artery wedge pressure, and maintains adequate cardiac output. This study set out to examine the poorly investigated area of if and how pre-treatment with LVAD impacts right ventricular (RV) function following OHT. METHODS AND RESULTS: We prospectively evaluated 59 (LVAD n = 20) consecutive OHT patients. Transthoracic echocardiography (TTE) was performed in conjunction with right heart catheterization (RHC) at 1, 6, and 12 months after OHT. RV function TTE-parameters included tricuspid annular plane systolic excursion (TAPSE), systolic tissue velocity (S'), fractional area change, two-dimensional RV global longitudinal strain and longitudinal strain from the RV lateral wall (RVfree). At 1 month after OHT, the LVAD group had significantly better longitudinal RV function than the non-LVAD group: TAPSE (15 ± 3 mm vs. 12 ± 2 mm, P < 0.001), RV global longitudinal strain (-19.8 ± 2.1% vs. -14.3 ± 2.8%, P < 0.001), and RVfree (-19.8 ± 2.3% vs. -14.1 ± 2.9%, P < 0.001). At this time point, pulmonary vascular resistance (PVR) was also lower [1.2 ± 0.4 Wood Units (WU) vs. 1.6 ± 0.6 WU, P < 0.05] in the LVAD group compared with the non-LVAD group. At 6 and 12 months, no difference was detected in any of the TTE and RHC measured parameters between the two groups. Between 1 and 12 months, all parameters of RV function improved significantly in the non-LVAD group but remained unaltered in the LVAD group. CONCLUSIONS: Our results indicate that pre-treatment with LVAD decreases PVR and is associated with significantly better RV function early following OHT. During the first year following transplantation, RV function progressively improved in the non-LVAD group such that at 6 and 12 months, no difference in RV function was detected between the groups.

Echocardiographic assessment of chamber size and ventricular function during the first year after heart transplantation.

AIMS: Detecting changes in ventricular function after orthotopic heart transplantation (OHT) using transthoracic echocardiography (TTE) is important but interpretation of findings is complicated by lack of data on early graft adaptation. We sought to evaluate echocardiographic measures of ventricular size and function the first year following OHT including speckle tracking derived strain. We also aimed to compare echocardiographic findings to haemodynamic parameters obtained by right heart catheterization (RHC). METHODS AND RESULTS: Fifty OHT patients were examined prospectively with TTE and RHC at 1, 6, and 12 months after OHT. Left ventricle (LV) was assessed with fractional shortening, ejection fraction and systolic tissue velocities. Right ventricular (RV) evaluation included tricuspid annular plane systolic excursion (TAPSE), systolic tissue velocity (S´) and fractional area change (FAC). LV global longitudinal and circumferential strain and RV global longitudinal strain (GLS) and RV lateral wall strain (RVfree) were analysed. No relevant changes occurred in LV echocardiographic parameters, whereas all measures of RV function improved significantly during follow-up. There was an increase in TAPSE (12.4 ± 3.3 mm to 14.4 ± 4.3 mm, p < .01), FAC (36% ± 8% to 41% ± 8%, p < .01), RV GLS (-15.8% ± 4% to -17.8% ± 3.6%, p < .01), and RVfree (-15.5% ± 3.7% to -18.6% ± 3.6%, p < .001). Between 1 and 12 months, pulmonary pressures decreased, whereas pulmonary vascular resistance did not. CONCLUSION: Stable OHT recipients reached steady state regarding LV function 1 month after transplantation. In contrast, RV function displayed gradual improvement the first year following OHT, indicating delayed RV adaptation as compared to the LV. Improved RV function parameters were independent of invasively measured pulmonary pressures.

Impact of gender on echocardiographic characteristics in heart transplant recipients.

AIMS: Assessment following heart transplantation (HTx) is routinely performed using transthoracic echocardiography. Differences in long-term mortality following HTx related to donor-recipient matching have been reported, but effects of gender on cardiac size and function are not well studied. The aims of this study were to evaluate differences in echocardiographic characteristics of HTx recipients defined by gender. METHODS AND RESULTS: The study prospectively enrolled 123 (n = 34 female) HTx recipients of which 23 recipients was donor-recipient gender mismatched. Patients were examined with 2-dimensional echocardiography using Philips iE33 ultrasound system. Data were analysed across strata based on recipient gender and gender mismatch. Male recipients had larger left ventricular (LV) mass, thicker septal wall (P<0·001) and larger absolute LV volumes (P<0·001). Mean LV ejection fraction (EF) was higher in females (P<0·05), but no differences in conventional parameters of right ventricular (RV) function were found. Ventricular strain was higher in females than in males: LV global longitudinal strain (P<0·01), RV global longitudinal strain (P<0·05) and RV lateral free wall (P<0·05). The male group receiving a female donor heart had comparable EF and strain parameters to the female group receiving a gender-matched heart. CONCLUSION: We found that female recipient gender was associated with smaller chamber size, higher LV EF and better LV and RV longitudinal strain. Gender-mismatched male recipients appeared to exhibit function parameters similar to gender-matched female recipients. Our results indicate that the gender aspect, analogous to current reference guidelines in general population, should be taken into consideration when examining patients post-HTx.

Permanent atrial fibrillation in patients without structural heart disease is not associated with signs of infection by Chlamydia pneumoniae and Helicobacter pylori.

OBJECTIVE: The objective of this study was to explore the role of Chlamydia pneumoniae and Helicobacter pylori infections in patients with idiopathic permanent atrial fibrillation. METHODS AND RESULTS: Sera from 72 patients with permanent atrial fibrillation without structural heart disease (mean age 69.6 years, 23 women) were analysed for IgG antibodies against Chlamydia pneumoniae and Helicobacter pylori and compared in a I:I age- and sex-matched case:control manner with those pooled from a healthy reference population of 72 individuals from the same geographical area. After excluding patients with other possible or definite factors known either to cause atrial fibrillation or to affect the prevalence of seropositivity to these agents, the frequency of seropositivity due to one or both of the infectious agents was compared. Serum C-reactive protein (CRP) level was assessed using immunoturbidimetry technique. Both agents were equally common in men and women. Neither seropositivity to Chlamydia pneumoniae (76% vs. 83%, patients vs. control subjects, ns) nor to Helicobacter pylori (57% contra 55%, patients vs. controls, ns) alone reached significance in the comparisons between patients with atrial fibrillation and control subjects. Serum CRP was higher in patients with AF (5.3 mg/L vs. 2.8 mg/L, P < 0.001). CONCLUSIONS: Though presence of permanent AF is associated with elevated CRP levels, this elevation is not the result of earlier infections with Chlamydia pneumoniae or Helicobacter pylori or their combination.

Discriminatory ability of right atrial volumes with two- and three-dimensional echocardiography to detect elevated right atrial pressure in pulmonary hypertension.

AIMS: Pulmonary hypertension (PH) patients have high mortality due to right ventricular failure. Predictors of poor prognostic outcome are increased right atrial volume (RAV) and elevated mean right atrial pressure (mRAP). Our aim was to determine whether RAV measured with 2D echocardiography (2DE) and 3D echocardiography (3DE) can detect elevated mRAP in patients evaluated for PH. METHODS: Of 85 patients prospectively evaluated for PH, 44 patients (63 ± 15 years, 57% female) had 2DE, 3DE and right heart catheterization within 48 h and were in sinus rhythm. Maximum (RAVmax ) and minimum (RAVmin ) volumes were measured with 3DE. 2D maximum RAV and RA area, inferior vena cava diameter and collapsibility were measured. Invasive mRAP > 8 mmHg was predefined as elevated. RESULTS: RAVmax and RAVmin correlated with mRAP (r = 0·40 and r = 0·35, P<0·05, for both), and so did 2DE maximum RAV (r = 0·42, P = 0·005) and RA area (r = 0·40, P = 0·008). Area under the curve (AUC) from receiver-operating characteristics curves was for 3DE 0·77 for RAVmax , 0·74 for RAVmin , from 2DE, 0·76 for maximum RAV and 0·75 for RA area to discriminate elevated mRAP (P<0·01 for all). PH patients had larger 3D RAV compared with controls (P<0·01). IVC diameter correlated with mRAP (r = 0·41, P = 0·007), but collapsibility did not (P = 0·078). AUC was neither significant for IVC diameter nor for collapsibility for predicting mRAP>8 mmHg. The optimal threshold was 57 ml m-2 for RAVmax , 31 ml m-2 for RAVmin and 36 ml m-2 for 2DE RAV. CONCLUSIONS: Enlarged RA measures with 2DE and 3DE have better discriminatory ability compared with IVC measures, to detect elevated mRAP in patients evaluated for PH.

Normal Reference Ranges for Transthoracic Echocardiography Following Heart Transplantation.

BACKGROUND: Heart function following heart transplantation (HTx) is influenced by numerous factors. It is typically evaluated using transthoracic echocardiography, but reference values are currently unavailable for this context. The primary aim of the present study was to derive echocardiographic reference values for chamber size and function, including cardiac mechanics, in clinically stable HTx patients. METHODS: The study enrolled 124 healthy HTx patients examined prospectively. Patients underwent comprehensive two-dimensional echocardiographic examinations according to contemporary guidelines. Results were compared with recognized reference values for healthy subjects. RESULTS: Compared with guidelines, larger atrial dimensions were seen in HTx patients. Left ventricular (LV) diastolic volume was smaller, and LV wall thickness was increased. With respect to LV function, both ejection fraction (62 ± 7%, P < .01) and global longitudinal strain (-16.5 ± 3.3%, P < .0001) were lower. All measures of right ventricular (RV) size were greater than reference values (P < .0001), and all measures of RV function were reduced (tricuspid annular plane systolic excursion 15 ± 4 mm [P < .0001], RV systolic tissue Doppler velocity 10 ± 6 cm/sec [P < .0001], fractional area change 40 ± 8% [P < .0001], and RV free wall strain -16.9 ± 4.2% [P < .0001]). Ejection fraction and LV global longitudinal strain were significantly lower in patients with previous rejection. CONCLUSION: The findings of this study indicate that the distribution of routinely used echocardiographic measures differs between stable HTx patients and healthy subjects. In particular, markedly larger RV and atrial volumes and mild reductions in both LV and RV longitudinal strain were evident. The observed differences could be clinically relevant in the assessment of HTx patients, and specific reference values should be applied in this context.

Right ventricular speckle tracking assessment for differentiation of pressure- versus volume-overloaded right ventricle.

BACKGROUND: Right ventricular (RV) dysfunction may be caused by either pressure or volume overload. RV function is conventionally assessed with echocardiography using tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (RVFAC), tricuspid lateral annular systolic velocity (S') and RV index of myocardial performance (RIMP). The purpose of this study was to evaluate whether RV global longitudinal strain (RVGLS) and RV-free wall strain (RV-free) could add additional information to differentiate these two causes of RV overload. METHODS AND RESULTS: The study enrolled 89 patients with an echocardiographic trans-tricuspid gradient >30 mmHg. Forty-five patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension (pressure overload) were compared with 44 patients with an atrial septum defect (volume overload). RV size was larger in the volume group (P<0·05). TAPSE and S' were lower in the pressure group (P<0·05, P<0·01). RVFAC was lower in the pressure group (P<0·001) as well as RVGLS (-12·1 ± 3·3% versus -20·2 ± 3·4%, P<0·001) and RV-free (-12·9 ± 3·3% versus -19·4 ± 3·4%, P<0·001). CONCLUSION: In this study, RVGLS and RV-free could more accurately discriminate RV pressure from volume overload than conventional measures. The reason could be that TAPSE and S' are unable to differentiate active deformation from passive entrainment caused by the left ventricle. The pressure group had evidence of marked RV hypertrophy despite standard functional parameters (TAPSE and S) within normal range. This would enhance the value of strain to more sensitively detect abnormal function. A cut-off value of below -16% for RVGLS and RV-free predicts RV pressure overload with high accuracy.

Age-related changes in P wave morphology in healthy subjects.

BACKGROUND: We have previously documented significant differences in orthogonal P wave morphology between patients with and without paroxysmal atrial fibrillation (PAF). However, there exists little data concerning normal P wave morphology. This study was aimed at exploring orthogonal P wave morphology and its variations in healthy subjects. METHODS: 120 healthy volunteers were included, evenly distributed in decades from 20-80 years of age; 60 men (age 50+/-17) and 60 women (50+/-16). Six-minute long 12-lead ECG registrations were acquired and transformed into orthogonal leads. Using a previously described P wave triggered P wave signal averaging method we were able to compare similarities and differences in P wave morphologies. RESULTS: Orthogonal P wave morphology in healthy individuals was predominately positive in Leads X and Y. In Lead Z, one third had negative morphology and two-thirds a biphasic one with a transition from negative to positive. The latter P wave morphology type was significantly more common after the age of 50 (P < 0.01). P wave duration (PWD) increased with age being slightly longer in subjects older than 50 (121+/-13 ms vs. 128+/-12 ms, P < 0.005). Minimal intraindividual variation of P wave morphology was observed. CONCLUSION: Changes of signal averaged orthogonal P wave morphology (biphasic signal in Lead Z), earlier reported in PAF patients, are common in healthy subjects and appear predominantly after the age of 50. Subtle age-related prolongation of PWD is unlikely to be sufficient as a sole explanation of this finding that is thought to represent interatrial conduction disturbances. To serve as future reference, P wave morphology parameters of the healthy subjects are provided.

A modified Ross operation to prevent pulmonary autograft dilatation.

A modification in Ross operation is described in which the free-standing pulmonary autograft root is suspended in a Dacron prosthetic vascular jacket with a view to prevent dilatation of the neo-aortic root. In a group of 13 patients operated consecutively using this technique, there was no significant increase in the diameters of the neo-aortic root after a mean 16-month follow-up. Aortic valve function remained also satisfactory.

Prediction of sinus rhythm maintenance following DC-cardioversion of persistent atrial fibrillation - the role of atrial cycle length.

BACKGROUND: Atrial electrical remodeling has been shown to influence the outcome the outcome following cardioversion of atrial fibrillation (AF) in experimental studies. The aim of the present study was to find out whether a non-invasively measured atrial fibrillatory cycle length, alone or in combination with other non-invasive parameters, could predict sinus rhythm maintenance after cardioversion of AF. METHODS: Dominant atrial cycle length (DACL), a previously validated non-invasive index of atrial refractoriness, was measured from lead V1 and a unipolar oesophageal lead prior to cardioversion in 37 patients with persistent AF undergoing their first cardioversion. RESULTS: 32 patients were successfully cardioverted to sinus rhythm. The mean DACL in the 22 patients who suffered recurrence of AF within 6 weeks was 152 +/- 15 ms (V1) and 147 +/- 14 ms (oesophagus) compared to 155 +/- 17 ms (V1) and 151 +/- 18 ms (oesophagus) in those maintaining sinus rhythm (NS). Left atrial diameter was 48 +/- 4 mm and 44 +/- 7 mm respectively (NS). The optimal parameter predicting maintenance of sinus rhythm after 6 weeks appeared to be the ratio of the lowest dominant atrial cycle length (oesophageal lead or V1) to left atrial diameter. This ratio was significantly higher in patients remaining in sinus rhythm (3.4 +/- 0.6 vs. 3.1 +/- 0.4 ms/mm respectively, p = 0.04). CONCLUSION: In this study neither an index of atrial refractory period nor left atrial diameter alone were predictors of AF recurrence within the 6 weeks of follow-up. The ratio of the two (combining electrophysiological and anatomical measurements) only slightly improve the identification of patients at high risk of recurrence of persistent AF. Consequently, other ways to asses electrical remodeling and / or other variables besides electrical remodeling are involved in determining the outcome following cardioversion.

Sequential characterization of atrial tachyarrhythmias based on ECG time-frequency analysis.

A new method for characterization of atrial arrhythmias is presented which is based on the time-frequency distribution of an atrial electrocardiographic signal. A set of parameters are derived which describe fundamental frequency, amplitude, shape, and signal-to-noise ratio. The method uses frequency-shifting of an adaptively updated spectral profile, representing the shape of the atrial waveforms, in order to match each new spectrum of the distribution. The method tracks how well the spectral profile fits each spectrum as well as if a valid atrial signal is present. The results are based on the analysis of a learning database with signals from 40 subjects, of which 24 have atrial arrhythmias, and an evaluation database with 211 patients diagnosed with atrial fibrillation. It is shown that the method robustly estimates fibrillation frequency and amplitude and produces spectral profiles with narrower peaks and more discernible harmonics when compared to the conventional power spectrum. The results suggest that a rather strong correlation exist between atrial fibrillation frequency and f wave shape. The developed set of parameters may be used as a basis for automated classification of different atrial rhythms.

Right ventricular performance after valve repair for chronic degenerative mitral regurgitation.

BACKGROUND: Our aim was to assess right ventricular (RV) performance after mitral valve repair by use of RV focused echocardiography and to evaluate the influence of elevated pulmonary artery systolic pressure (PASP) on RV recovery. METHODS: Forty consecutive patients undergoing mitral valve repair were prospectively investigated with RV focused echocardiography, including two-dimensional speckle tracking-derived longitudinal strain and measurement of N-terminal protype-B natriuretic peptide levels performed on the day before operation and 6 months postoperatively. RESULTS: The 30-day mortality was 0%. Overall survival was 97.5% ± 2.5% at 6-month follow-up, and the prevalence of postoperative RV dysfunction was 61% (n = 22). Conventional longitudinal indices of RV function decreased significantly after operation (n = 36): tricuspid annular plane systolic excursion (mean 24 ± 5 mm vs mean 15 ± 3 mm, p < 0.001), systolic peak velocity (mean 14 ± 3 cm/s vs mean 10 ± 2 cm/s, p < 0.001), isovolumic acceleration time (mean 2.5 ± 1.0 cm/s(2) vs mean 2.1 ± 0.7 cm/s(2), p = 0.022), but the RV free wall, septal, and global strain did not change significantly. Patients with preoperative PASP above 50 mm Hg showed a significant change in postoperative RV global strain compared with those whose PASP was 50 mm Hg or below (mean difference 10% ± 30% vs -17% ± 23%, p = 0.033). CONCLUSIONS: RV dysfunction was common at 6-month follow-up. Pulmonary hypertension, although reversible after operation, had a negative effect on RV function. Speckle tracking-derived RV strain may assist in the prioritization of surgical referrals to avoid biventricular impairment.