Left atrial size and function as predictors of new-onset of atrial fibrillation in patients with asymptomatic aortic stenosis: the simvastatin and ezetimibe in aortic stenosis study

The Added Value of Atrial Strain Assessment in Clinical Practice

Speckle tracking echocardiography has emerged as a sensitive tool to analyze myocardial function with improved diagnostic accuracy and prognostic value. Left atrial strain assessment has become a novel imaging method in cardiology with superior prognostic value compared to conventional left atrial volume indices. Left atrial function is divided into three phases, reservoir function being the most important. This review summarizes the added value of speckle tracking echocardiography derived left atrial strain assessment in clinical practice. Recently published data suggest the prognostic value of left atrial reservoir function in heart failure, atrial fibrillation, stroke and valvular heart disease. Furthermore, left atrial reservoir strain proved to be a predictor of cardiovascular morbidity and mortality in the general population. Thus, routine assessment of left atrial function can be an optimal strategy to improve cardiovascular risk prediction and supplement the current risk prediction models.

Aortic valve calcification among elderly males from the general population, associated echocardiographic findings, and clinical implications

AIMS

Aortic valve calcification (AVC) detected by non-contrast computed tomography (NCCT) associates with morbidity and mortality in patients with aortic valve stenosis. However, the importance of AVC in the general population is sparsely evaluated. We intend to describe the associations between AVC score on NCCT and echocardiographic findings as left atrial (LA) dilatation, left ventricular (LV) hypertrophy, aortic valve area (AVA), peak velocity, mean gradient, and aortic valve replacement (AVR) in a population with AVC scores ≥300 AU.

METHODS AND RESULTS

Of 10 471 males aged 65-74 years from the Danish Cardiovascular Screening trial (DANCAVAS), participants with AVC score ≥300 AU were invited for transthoracic echocardiography and 828 (77%) of 1075 accepted the invitation. AVC scores were categorized (300-599, 600-799, 800-1199, and ≥1200 AU). AVR was obtained from registries. AVC was significantly associated with a steady increase in LA dilation (10.5%, 16.3%, 15.8%, 19.6%, P = 0.031), LV hypertrophy (3.9%, 6.6%, 8.9%, 10.1%, P = 0.021), peak velocity (1.7, 1.9, 2.1, 2.8 m/s, P = 0001), mean gradient (6, 8, 11, 19 mmHg, P = 0.0001), and a decrease in AVA (2.0, 1.9, 1.7, 1.3 cm2, P = 0.0001). The area under the curve was 0.79, 0.93, and 0.92 for AVA ≤1.5 cm2, peak velocity ≥3.0 m/s, and mean gradient ≥20 mmHg, respectively, and the associated optimal AVC score thresholds were 734, 1081, and 1019 AU. AVC > 1200 AU was associated with AVR (P < 0.0001).

CONCLUSION

Among males from the background population, increasing AVC scores were associated with LA dilatation, LV hypertrophy, AVA, peak aortic velocity, mean aortic gradient, and AVR.

Can echocardiography improve the prediction of thromboembolic risk in atrial fibrillation? Evidences and perspectives

Atrial fibrillation is the most common arrhythmia and its prevalence is expected to further increase. Patients with atrial fibrillation have an increased risk of stroke (fivefold increased risk), heart failure, and death. In patients with non-valvular atrial fibrillation, the most recent guidelines recommend the use of the CHA₂DS₂-VASc (congestive heart failure, arterial hypertension, age > 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65-74 years, sex category) scoring system to identify those who may benefit from oral anticoagulant treatment. Guidelines recommend initiation of oral anticoagulation with vitamin K antagonists or direct oral anticoagulants in men with a score ≥ 2 and in women with a score ≥ 3, while oral anticoagulation in individuals with a score of 0 is not recommended. Accordingly, men with CHA₂DS₂VASc score = 1 (and women with CHA₂DS₂VASc = 2) represent a grey zone where guidelines do not provide a definite oral anticoagulant indication. Implementation of risk stratification with transthoracic echocardiography could be extremely useful. Both prospective and observational studies using transthoracic echocardiography prediction of events and studies utilizing transesophageal echocardiographic parameters as surrogate markers of thromboembolic events make sustainable the hypothesis that echocardiography could improve thromboembolism prediction in non-valvular atrial fibrillation. However, because of some controversial results of different studies, determination of the best echocardiographic parameter predicting thromboembolic events in atrial fibrillation remains uncertain. The combination of left atrial enlargement with left atrial function (in particular assessing left atrial strain) appears to be very valuable, but needs to be confirmed in large-scale multi-center trials.

Left Atrial Function Determined by Cardiac Computed Tomography Predicts Device-Detected Atrial High-Rate Episodes in Patients Treated With Cardiac Resynchronization Therapy

OBJECTIVE

The objective of this study was to examine whether left atrial (LA) volumes and function were associated with atrial high-rate episodes (AHREs) in patients with cardiac resynchronization therapy (CRT).

METHODS

Ninety-two consecutive patients without prior atrial fibrillation underwent clinical evaluation, echocardiograms, and cardiac computed tomography (CT) before CRT implantation and after 6 months. Left atrial volumes and LA emptying fraction (LAEF) were derived by CT images reconstructed at 5% phase increments of the cardiac cycle. Cox regression was used to assess associations between AHRE and LA anatomical and functional variables.

RESULTS

Twenty-two patients (24%) developed AHRE during 1.9 years (SD, 1 year) At baseline, higher LAEF was associated with a lower risk of AHRE (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.91-0.98; P = 0.003), and large LA minimal (LAmin) volume was related to higher risk of AHRE (HR, 1.03; 95% CI, 1.00-1.06; P = 0.04). When combining LAEF and LAmin volume, only LAEF remained associated with occurrence of AHRE. Higher passive LAEF was associated with lower risk of AHRE (HR, 0.95; 95% CI, 0.91-0.98; P = 0.003).

CONCLUSIONS

In patients with CRT, low preimplant LAEF measured by cardiac CT was independently associated with device-detected AHRE.

The effect of P wave indices on new onset atrial fibrillation after trans-catheter aortic valve replacement

OBJECTIVES

Data is scarce regarding the relation between P wave indices and new onset atrial fibrillation (NOAF) after trans-catheter aortic valve replacement (TAVR).

AIMS

The present study aimed to find out certain characteristics of P wave that may predict NOAF after TAVR procedure.

METHOD

Patients with severe calcific aortic stenosis who had undergone TAVR procedure between 2013 and 2019 in two centers were investigated. P wave abnormalities that have been resumed to reflect impaired atrial conduction; partial and advanced inter atrial block (IAB), P-wave terminal force in lead V1, P wave dispersion, reduced amplitude of P- wave in lead I, P wave peak time in D2 and V1 were evaluated on pre- procedural 12 derivation surface electrocardiography (ECG). The relationship between these parameters and incidence of NOAF during index hospitalization was evaluated.

RESULTS

A total of 227 consecutive patients (median age 79 [74-83]; 134 [59%] female) were included in the study. NOAF occurred in 46 (20.3%) patients. P wave duration, P wave dispersion, number of patients with partial and advanced IAB, left atrium diameter, STS score were higher in NOAF patients. Use of general anesthesia and history of prior open heart surgery were also more frequent in NOAF group. In multivariable logistic regression analysis; advanced IAB (OR 6.413 [2.555-16.095] p < 0.01), P wave dispersion (OR 3.544 [1.431-8.780] p = 0.006) and use of general anesthesia (OR 2.736 [1.225-6.109] p = 0.014) were independent predictors of NOAF.

CONCLUSION

Among P wave abnormalities evaluated on pre-procedural 12-derivation surface ECG, advanced IAB and P wave dispersion may predict NOAF after TAVR procedure.

Significance of early recurrence of atrial fibrillation after catheter ablation: a nationwide Danish cohort study

BACKGROUND

Recurrence of atrial tachyarrhythmias after ablation of atrial fibrillation (AF) is common, although consensus guidelines advise against immediate re-ablation of "early recurrences" (occurring ≤ 90 days after ablation). However, recent studies show early recurrence is associated with "late recurrence" (occurring > 90 days) and question the duration of this "blanking period." We investigated incidence and timing of early recurrence in relation to late recurrence in a large nationwide cohort.

METHODS

From Danish nationwide registers, we included all patients aged 18 and older who underwent first-time ablation for AF between January 2005 and April 2017 and followed them for up to 2 years.

RESULTS

Of the total 7339 patients included (72% male; median age 62 years), 2801 (38%) experienced early recurrence. The odds of late recurrence were 2.34 times higher (95% confidence interval, 2.09-2.63; P < 0.001) given early recurrence, compared with those without early recurrence. In particular, both timing and frequency of early recurrences were associated with a significantly higher odds of late recurrence in a graded relationship: odds ratio (OR) 2.08/4.96/6.25 for early recurrences in the first/second/third month respectively (all P < 0.001); and OR 1.64/2.83/5.14 for those experiencing one/two/more than two episodes respectively (all P < 0.001); compared with those without early recurrence.

CONCLUSION

In patients undergoing first-time ablation for AF, both the frequency and later onset of early recurrence are significantly associated with higher odds of late recurrence. This suggests the arbitrary blanking period should be abandoned in favor of a case-by-case assessment when evaluating candidates for re-ablation.

Tissue Doppler imaging of the atrial lateral wall: Correlation with atrial strain rate and parameters of diastolic function

OBJECTIVE

To evaluate the velocity profile of the lateral wall of the left atrium (LA) using pulsed-wave color tissue Doppler imaging (TDI) on line and its correlation with two-dimensional strain rate imaging (SRI) by speckle tracking, of equal segments and phases, and other parameters of diastolic function in a population of individuals without known cardiovascular disease.

MATERIALS AND METHODS

A total of 91 adults aged 18-74 years, without cardiovascular history, hypertension, diabetes, dyslipidemia or obesity, were evaluated. A Doppler echocardiogram was performed. The lateral wall of the LA was divided subjectively into three portions, the atrial roof was excluded; the peak velocities of the basal and midportions, and their average, were measured with pulsed-wave TDI on line and SRI. Using both techniques, a first positive wave (S'la and SRS-reservoir phase) and two negative waves (E'la and SRE-conduit phase-and A'la and SRA-atrial systole-respectively) were obtained. E'la/A'la ratio and SRE/SRA ratio were analyzed.

RESULTS

The median age was 42 years, and 54.9% of the subjects were female. S'la presented moderate correlation with S' lateral mitral annulus. Both E'la and the E'la/A'la relationships showed moderate to good correlation with various diastolic dysfunction parameters evaluated and SRI. A'la did not present a statistically significant correlation with any of the variables evaluated.

CONCLUSION

Evaluation of the lateral wall of the LA by pulsed-wave color TDI on line is feasible in the vast majority of patients. In the conduit phase, E'la and the E'la/A'la relationship showed correlation with the parameters that evaluate diastolic function and SRI.

Atrial fibrillation in patients undergoing transcatheter aortic valve implantation: epidemiology, timing, predictors, and outcome

Atrial fibrillation (AF) is a common arrhythmia in patients with aortic stenosis. When these patients are treated medically or by surgical aortic valve replacement, AF is associated with increased risk of adverse events including death. Growing evidence suggests a significant impact of AF on outcomes also in patients with aortic valve stenosis undergoing transcatheter aortic valve implantation (TAVI). Conversely, limited evidence is available regarding the optimal management of this condition. This review aims to summarize prevalence, pathophysiology, prognosis, and treatment of AF in patients undergoing TAVI.

Prognostic value of area of calcified aortic valve by 2-dimensional echocardiography in asymptomatic severe aortic stenosis patients with preserved left ventricular ejection fraction

We hypothesized that area of calcified aortic valve (ACAV) measured by 2D echocardiography (2DE) can predict future cardiovascular events in asymptomatic severe aortic stenosis (AS).Multidetector computed tomography determined aortic valve calcification load is strongly associated with AS severity but has risks for radiation exposure. Quantification of ACAV by transthoracic 2DE is simple and convenient but its clinical utility has not been extensively studied.We measured ACAV in 124 asymptomatic severe AS patients (80 ± 9 years, 45 males) with preserved left ventricular ejection fraction. ACAV was measured by planimetry from 2D zoomed long axis view of the AV at end-diastole. Patients were followed to record cardiac death (CD) and major adverse cardiovascular events (MACEs).During a median follow-up of 232 days, 17 patients had MACE, including 8 CD. ACAV was significantly larger in patients with event compared to those without (1.14 ± 0.35 cm vs 0.87 ± 0.34 cm, P=.0032). Using receiver operating characteristics derived ACAV of 0.79 cm as cutoff value, Kaplan-Meyer analysis showed it could discriminate high-risk group from low-risk group for future CD (P=.0223, χ = 5.22) and MACE (P = .0054, χ = 7.74).2DE determined ACAV is straightforward and has potential to predict future cardiac events in asymptomatic severe AS patients.

Atrial volume and function during exercise in health and disease

BACKGROUND

Although atrial function has prognostic significance in many cardiovascular conditions, changes during exercise have not previously been assessed. The aim of this study was to evaluate left atrial (LA) and right atrial (RA) volume and function during incremental exercise, both in normal individuals, healthy athletes, and in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

Fifteen healthy non-athletes, 15 athletes and 15 CTEPH patients underwent multi-slice real-time cardiovascular magnetic resonance imaging at rest and during supine bicycle exercise with simultaneous invasive hemodynamic measurements.

RESULTS

At rest, athletes had larger indexed maximal RA and LA volumes (iRAVmax, iLAVmax) than CTEPH patients and non-athletes, the latter two groups having similar values. CTEPH patients had lower RA and LA emptying functions (EmF) at rest. During exercise, RA volumes (maximum and minimum) increased in CTEPH patients, whilst decreasing in athletes and non-athletes (P < 0.001). The exercise-induced change in iLAVmax was similar between groups, but iLAVmin did not decrease in CTEPH patients. Thus exercise-induced increases in RAEmF and LAEmF, as seen in normal physiology, were significantly impaired in CTEPH patients. At peak exercise, RA volumes (maximum and minimum) and EmF correlated strongly with RA pressure (R = 0.70; P = 0.005; R = 0.83; P < 0.001; R = -0.87; P < 0.001). On multivariate analysis, peak exercise RAEmF and iLAVmin were independent predictors of VO2peak in CTEPH patients and together explained 72% of the variance in VO2peak (ß =0.581 and ß = -0.515, respectively).

CONCLUSIONS

In normal physiology, RAEmF and LAEmF increase with exercise, whereas CTEPH patients have impaired LAEmF and RAEmF, which becomes more apparent during exercise. Therefore, the changes in atrial volumes and function during exercise enable a far better distinction between physiological and pathological atrial remodeling than resting measures of volumes which are prone to confounding factors (e.g. endurance training). Peak exercise RAEmF is a good marker of poor functional state in CTEPH patients.

Antihypertensive Treatment With β-Blockade in Patients With Asymptomatic Aortic Stenosis and Association With Cardiovascular Events

Background

Patients with aortic stenosis (AS) often have concomitant hypertension. Antihypertensive treatment with a β‐blocker (Bbl) is frequently avoided because of fear of depression of left ventricular function. However, it remains unclear whether antihypertensive treatment with a Bbl is associated with increased risk of cardiovascular events in patients with asymptomatic mild to moderate AS.

Methods and Results

We did a post hoc analysis of 1873 asymptomatic patients with mild to moderate AS and preserved left ventricular ejection fraction in the SEAS (Simvastatin and Ezetimibe in Aortic Stenosis) study. Propensity‐matched Cox regression and competing risk analyses were used to assess risk ratios for all‐cause mortality, sudden cardiac death, and cardiovascular death. A total of 932 (50%) patients received Bbl at baseline. During a median follow‐up of 4.3±0.9 years, 545 underwent aortic valve replacement, and 205 died; of those, 101 were cardiovascular deaths, including 40 sudden cardiovascular deaths. In adjusted analyses, Bbl use was associated with lower risk of all‐cause mortality (hazard ratio 0.5, 95% confidence interval 0.3‐0.7, P<0.001), cardiovascular death (hazard ratio 0.4, 95% confidence interval 0.2‐0.7, P<0.001), and sudden cardiac death (hazard ratio 0.2, 95% confidence interval 0.1‐0.6, P=0.004). This was confirmed in competing risk analyses (all P<0.004). No interaction was detected with AS severity (all P>0.1).

Conclusions

In post hoc analyses Bbl therapy did not increase the risk of all‐cause mortality, sudden cardiac death, or cardiovascular death in patients with asymptomatic mild to moderate AS. A prospective study may be warranted to determine if Bbl therapy is in fact beneficial.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00092677.

The influence of clinical and genetic factors on left ventricular wall thickness in Ragdoll cats

OBJECTIVES

To investigate the effect of various genetic and environmental modifiers on left ventricular (LV) wall thickness in a cohort of cats genotyped for the myosin binding protein C3 mutation (MYBPC3).

ANIMALS

Sixty-four Ragdoll cats.

METHODS

All cats were screened for HCM with echocardiography and genotyping for the HCM-associated MYBPC3:R820W mutation. Cats were also genotyped for previously identified variant polymorphisms of the angiotensin-converting enzyme (ACE) and cardiac beta-adrenergic receptor (ADRB1) genes. Plasma N-terminal pro-B-type natriuretic peptide and cardiac troponin I were also measured. Associations were evaluated between genotype (MYBPC3 negative/positive, and ACE and ADRB1 negative/heterozygous/homozygous), patient factors (body weight, age and sex) and echocardiographic measurements of LV wall thickness.

RESULTS

Male cats had greater maximum wall thickness (LVmax; 5.8 mm, IQR 5.1-6.4 mm) than females (4.7 mm, IQR 4.4-5.3 mm, p = 0.002). Body weight positively correlated with LVmax (ρ = 0.604, p < 0.001). The MYBPC3:R820W-positive cats had a greater LVmax (5.44 mm, IQR 4.83-6.28 mm) than the negative cats (4.76 mm, IQR 4.36-5.32 mm, p = 0.001). Also, the ACE polymorphism genotype was associated with LVmax: the homozygous cats (5.37 mm, IQR 5.14-6.4 mm) had greater LVmax than the heterozygous cats (4.73 mm, IQR 4.41-5.55 mm, p = 0.014). Only the MYBPC3 genotype and body weight were independently associated with wall thickness in multivariable analysis.

CONCLUSIONS

This study provides evidence that the MYBPC3:R820W mutation is independently associated with LV wall thickness in Ragdoll cats. Body weight is also independently associated with maximum LV wall thickness, but is not currently accounted for in HCM screening. In addition, other genetic modifiers may be associated with variation in LV wall thickness in Ragdolls.

Impact of gout on the risk of atrial fibrillation

OBJECTIVES

To examine the risk of atrial fibrillation (AF) at the time of first diagnosis of gout compared with matched controls and to follow incident gout patients and their matched controls after diagnosis to compare their subsequent risk of AF.

METHODS

From the UK Clinical Practice Research Data-link, 45 378 incident gout patients and 45 378 age-, sex-, practice-, registration year- and index year-matched controls were identified. Index dates were initial diagnosis date for gout patients and their matched controls. The risk of AF at diagnosis [odds ratios (ORs), using conditional logistic regression] and after the diagnosis of gout [hazard ratios (HRs), using Cox proportional models] were estimated, adjusted for BMI, smoking, alcohol consumption, ischaemic heart disease, heart failure, heart valve disease, hyperthyroidism and other comorbidities and medications.

RESULTS

The prevalence of AF at index date in gout patients (male, 72.3%; mean age, 62.4 ± 15.1 years) was 7.42% (95% CI 7.18, 7.66%) and in matched controls 2.83% (95% CI 2.67, 2.98%). The adjusted OR (95% CI) was 1.45 (1.29, 1.62). The cumulative probability of AF at 1, 2, 5 and 10 years after index date was 1.08, 2.03, 4.77 and 9.68% in gout patients and 0.43, 1.08, 2.95 and 6.33% in controls, respectively (log-rank test, P < 0.001). The adjusted HR (95% CIs) was 1.09 (1.03, 1.16).

CONCLUSION

This population-based study indicates that gout is independently associated with a higher risk of AF at diagnosis and the risk is also higher after the diagnosis.

Determinants and prognosis of atrial fibrillation in patients with aortic stenosis

Atrial fibrillation (AF) is frequently encountered in patients with aortic stenosis (AS) and its incidence also increases with age. In the general population, AF is known to increase cardiovascular risk. We sought to investigate the prognostic importance of AF associated with AS in the context of routine clinical practice. This analysis was based on 809 patients (75 ± 12 years) diagnosed with AS (aortic valve area <2 cm(2)) and normal (≥50%) ejection fraction (EF). Patients were grouped according to the presence of sinus rhythm (SR) or AF at study enrollment. The AF group comprised 141 patients (17.5%) with AF, whereas 668 patients (82.5%) were in SR at inclusion. Four-year estimates of all-cause mortality with medical and surgical management were 60 ± 5% for the AF group compared with 24 ± 2% for the SR group (p = 0.0001). On multivariate analysis, the risk of all-cause mortality was higher in the AF group than in the SR group (adjusted hazard ratio [HR] 2.47 [1.83 to 3.33], p = 0.0001). AF remained associated with excess mortality risk when the analysis was limited to asymptomatic patients (adjusted HR 2.31 [1.38 to 3.89], p = 0.002) and, respectively, patients with severe AS (adjusted HR 2.22 [1.41 to 3.49], p = 0.001). Among patients managed medically, AF was independently associated with increased risk of death in the overall study population (adjusted HR 2.52 [1.81 to 3.51], p = 0.0001), in asymptomatic AS (adjusted HR 2.12 [1.19 to 3.76], p = 0.01), and in severe AS (adjusted HR 2.23 [1.30 to 3.81], p = 0.004). In conclusion, AF is a major predictor of mortality, in both medically and surgically managed patients with AS, irrespective of the functional status and the severity. AF is, therefore, a strong marker of risk in AS and should be considered for clinical decision making.

Impact of atrial fibrillation on outcomes in patients who underwent transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) has emerged as an alternative treatment for surgical high-risk patients with severe aortic stenosis. The aim of this study was to determine the impact of atrial fibrillation (AF) on procedural outcomes. Data from 137 patients who underwent TAVR using Edwards SAPIEN valve were reviewed. The predictors of new-onset atrial fibrillation (NOAF) after the procedure were analyzed. In addition, the post-TAVR clinical outcomes and adverse events were compared according to the presence and absence of preprocedural and postprocedural AF. Previous AF was present in 49% of the patients who underwent TAVR. After the procedure, NOAF was detected in 21% of patients, and the cumulative incidence of post-TAVR AF was 60%. After TAVR, 50% of all the episodes of NOAF occurred in the initial 24 hours after the procedure. Transapical approach was observed to an important predictor of NOAF (adjusted odds ratio [OR] 5.05, 95% confidence interval [CI] 1.40 to 18.20, p = 0.013). The composite outcome of all-cause mortality, stroke, vascular complications, and repeat hospitalization in 1 month after TAVR was significantly higher in patients with previous AF (33 of 67 vs 19 of 70, adjusted OR 2.60, 95% CI 1.22 to 5.54, p = 0.013) compared with patients who did not have previous AF. The presence of post-TAVR AF led to a prolongation in the duration of intensive care unit stay by an average of 70 hours (95% CI 25 to 114.7 hours, p = 0.002). Similarly, post-TAVR AF also led to the prolongation in the hospital stay by an average of 6.7 days (95% CI 4.69 to 8.73 days, p <0.0005). In conclusion, our study demonstrates that the presence of AF before TAVR is an important predictor of the composite end point of all-cause mortality, stroke, vascular complications, and repeat hospitalization in 1 month after the procedure. AF after TAVR is more likely to be encountered with the transapical approach and is associated with a prolongation of intensive care unit and hospital stay.

Plasma cardiac troponin I concentration and cardiac death in cats with hypertrophic cardiomyopathy

BACKGROUND

The use of cardiac biomarkers to assist in the diagnosis of occult and symptomatic hypertrophic cardiomyopathy (HCM) in cats has been established. There is limited data describing their prognostic utility in cats with HCM.

HYPOTHESIS

Circulating concentrations of N-terminal B-type natriuretic peptide (NTproBNP) and cardiac troponin I (cTnI) predict cardiac death in cats with HCM.

ANIMALS

Forty-one cats diagnosed with HCM at a veterinary teaching hospital, between February 2010 and May 2011.

METHODS

Prospective investigational study. Plasma samples were collected from cats diagnosed with HCM and concentrations of NTproBNP and cTnI were analyzed at a commercial laboratory. Echocardiographic measurements from the day of blood sampling were recorded. Long-term outcome data were obtained. Associations with time to cardiac death were analyzed using Cox proportional hazards models.

RESULTS

When controlling for the presence/absence of heart failure and echocardiographic measures of left atrial size and function, cTnI > 0.7 ng/mL was independently associated with time to cardiac death. In univariable analysis, NTproBNP > 250 pmol/L was associated with cardiac death (P = .023), but this did not remain significant (P = .951) when controlling for the effect of clinical signs or left atrial size/function.

CONCLUSIONS AND CLINICAL IMPORTANCE

Plasma concentration of cTnI (cutoff >0.7 ng/mL) is a predictor of cardiac death in cats with HCM that is independent of the presence of heart failure or left atrial dilatation.