Ventricular-arterial coupling predicts outcomes in adults with a systemic right ventricle

Background

Patients with a systemic right ventricle (SRV) and biventricular circulation experience high incidence of cardiovascular morbidities and decreased survival [1]. Non-invasive measures of subclinical ventricular dysfunction are needed to appropriately identify patients at increased risk for adverse outcomes. Ventricular-arterial coupling (VAC), the ratio between the effective arterial elastance (Ea) and ventricular end-systolic elastance (Ees), may predict clinical outcomes in patients with SRV [2].

Objectives

To assess VAC in adults with SRV and evaluate its correlation with clinical outcomes.

Methods

Consecutive cardiovascular magnetic resonance (CMR) examinations of adults with D-loop transposition of great arteries (TGA) after atrial switch operation and L-loop TGA performed at Boston Children's Hospital between 2005 and 2019 were analyzed. VAC was calculated as Ea/Ees (Ea = mean arterial blood pressure (MBP)/ventricular stroke volume; Ees = MBP/end-systolic volume). Global myocardial strain was measured by feature tracking analysis on cine steady-state free precession sequences. Cox proportional hazards regression analysis was performed to assess the association of SRV functional parameters with clinical outcomes. The analysis was adjusted for age, sex, and body mass index. The primary outcome was defined as a composite of death, cardiovascular arrest, hospitalizations for heart failure (HF); the secondary outcome as atrial arrhythmias; the tertiary outcome included other causes of cardiovascular hospitalizations (percutaneous or surgical interventions, device implantation, other cardiovascular disease). Cumulative incidence of the study outcomes was estimated using Kaplan-Meier method.

Results

One hundred sixty-seven adults (mean age 32±10 years, 59% men) with SRV were analyzed. Patients with HF (n=48, 29%) had higher VAC values as compared to those without HF (1.4±0.8 vs. 1.1±0.5, p=0.01). Over a mean follow-up of 6.5±4.2 years, 15 over 139 patients (11%) experienced the primary outcome with an incidence rate of 1.7 per 100 patient-years (95% confidence interval (CI), 1.04–2.85). Higher VAC values were significantly associated with an increased risk of the primary outcome (p for trend = 0.01, Figure 1). VAC was the only functional parameter associated with the primary outcome (hazard ratio (HR) 1.99, 95% CI: 1.06–3.73, p=0.031), secondary outcome (HR 2.33, 95% CI: 1.12–4.82, p=0.023) and tertiary outcome (HR 1.63, 95% CI: 1.09–2.44, p=0.018) in the adjusted analysis (Table 1). Ejection fraction (EF) was not associated with the study outcomes in the adjusted analysis (p>0.05, Table 1) whereas global circumferential and radial strain showed an association limited to the tertiary endpoint (p=0.004, Table 1).

Conclusions

CMR-derived VAC is associated with adverse outcomes in SRV patients and may improve risk stratification of this unique population.

Funding Acknowledgement

Type of funding sources: None.

A comprehensive study of the incremental prognostic value of novel biomarkers in PARADIGM-HF (Bio-PREDICT-HF)

Background

Although multiple novel biomarkers have individually been shown to predict outcomes in patients with HFrEF, the value of these over and above conventional clinical and laboratory variables, plus natriuretic peptides, is uncertain.

Purpose

To test the incremental predictive value of 11 novel biomarkers added to a recent prognostic model 1 (PREDICT-HF) derived in PARADIGM-HF and validated in ATMOSPHERE and the Swedish heart failure registry. The PREDICT-HF model includes clinical variables, standard laboratory variables, and BNP or NT-proBNP.

Methods

1559 participants enrolled in PARADIGM-HF had all 11 biomarkers of interest measured. These reflected different pathophysiological pathways: (i) myocyte injury (high sensitivity cardiac troponin T), (ii) cardiac remodelling and inflammation (growth stimulation expressed gene 2, growth differentiation factor-15 and galectin-3), (iii) extracellular matrix remodelling (matrix metalloproteinase-2, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1), (iv) neurohormonal pathways (aldosterone) and (v) renal dysfunction and injury (cystatin C, kidney injury molecule-1 and urinary albumin to creatinine ratio). The incremental prognostic value of these biomarkers was evaluated using Harrell's C statistic.

Results

The mean age of participants studied was 67.3 (SD 9.9) years, 1254 (80%) were men and 1103 (71%) were in NYHA class II. During a median follow-up of 31 months, 197 patients died and 300 experienced the primary composite outcome (cardiovascular death or heart failure hospitalization).

When each candidate biomarker (log unit) was added individually to the PREDICT-HF base model, GDF-15, ST2, TIMP1, cystatin C, hsTnT and UACR were independent predictors of all-cause mortality (Table 1). GDF-15, TIMP1, hs-TnT and cystatin C consistently increased the risk of both all-cause mortality and the primary outcome. Individuals who had all 4 biomarkers elevated (compared to none elevated) had the highest risk: HR for all-cause mortality 3.65 (2.01–6.64), p<0.0001. Adding these 4 biomarkers to the baseline PREDICT HF model improved the C statistic for all-cause mortality from 0.726 to 0.745.

Conclusion

Several novel biomarkers provide meaningful additional prognostic information in patients with HFrEF. A multimarker approach incorporating biomarkers reflecting different pathophysiological pathways added most information. This approach may be useful in refining risk and targeting treatment.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The PARADIGM-HF trial was funded by Novartis.J.J.V.M is supported by a British Heart Foundation Centre of Excellence Grant

History of stroke in patients with heart failure: prevalence, baseline characteristics and clinical outcomes

Background

Stroke is an important but neglected comorbidity in patients with heart failure (HF). Little is known about the characteristics and outcomes of HF patients with a history of stroke.

Purpose

To examine the prevalence of prior stroke in patients with HF and reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), the clinical characteristics of patients with a history of stroke, and the clinical outcomes in patients with prior stroke compared to those without.

Methods

Individual patient data analysis using three recent HFrEF trials (ATMOSPHERE, PARADIGM-HF, and DAPA-HF) and HFpEF trials (CHARM-Preserved, I-Preserve, TOPCAT-Americas, and PARAGON-HF). Cox regression was used to analyze clinical outcomes.

Results

Among 20159 HFrEF patients enrolled, 1683 (8.3%) had a history of stroke and among the 13252 patients with HFpEF 1287 (9.7%) had a prior stroke. Compared to patients without stroke, those with stroke were slightly older and more likely to have a history of hypertension, myocardial infarction, atrial fibrillation, diabetes, carotid artery disease, and peripheral artery disease (for both HFrEF and HFpEF). Patients with a history of stroke had worse NYHA class and KCCQ scores, and a higher rate of fatigue; they also had a higher median NT-proBNP level and lower eGFR than those without prior stroke (whether HFrEF or HFpEF). Systolic BP, pulse pressure and LVEF did not differ susbtantialy between patients with and without a history of stroke. The table shows outcomes according to history of stroke or not, stratified by LVEF phenotype. During follow-up, all fatal and non-fatal outcomes were significantly more common in patients with a history of stroke. The augmentation of risk tended to be greater in patients with HFpEF than HFrEF, but was not statistically different.

Conclusion

Approximately 1 in 11 patients in recent HF trials had a history of stroke and these patients were at higher risk of fatal and non-fatal events than those without prior stroke. HF hospitalization as well as atherothrombotic events (myocardial infarction and stroke) were more common among patients with prior stroke – patients with prior stroke had at least 30% higher risk of all events examined, regardless of LVEF, and more than double incidence of repeat stroke.

Funding Acknowledgement

Type of funding sources: Other.

Stroke in patients with heart failure and reduced ejection fraction without atrial fibrillation: external validation of a risk model

Background

Heart failure (HF) ranks only second to atrial fibrillation (AF) as a cause of cardio-embolic stroke. Although anticoagulation reduces this risk in HF patients not in AF, the risk/benefit profile in relatively unselected populations is not favourable. Identification of patients at high risk of stroke may allow targeted and safer use of prophylactic anticoagulant therapy. Previously, we proposed a simple risk model for stroke in patients with HF and reduced ejection fraction (HFrEF). However, this model was derived from the two older trials (published in 2007/2008) and was not externally validated.

Purpose

We aimed to evaluate the current incidence of stroke in patients with HFrEF not in AF receiving modern pharmacological therapy and to validate our stroke prediction model.

Methods

We examined patient-level data from the PARADIGM-HF, ATMOSPHERE, and DAPA-HF trials. The risk score was calculated following: 7.39×(insulin-treated diabetes) + 6.53×(previous stroke) + 2.80×[ln(NT-proBNP (pg/ml)) × 0.1182]). According to the tertile of risk score, we divided the patients into three groups. Patients with AF were defined as those with either AF on an ECG or a history of AF.

Results

Of the total of 20,159 patients (who experienced 590 strokes) enrolled in the three trials, 12,751 patients did not have AF at baseline. Of those, 1,143 patients (9%) had insulin-treated diabetes, 873 patients (6.8%) had a history of the previous stroke, and the median value of NT-proBNP was 1,243 pg/ml. During a median follow-up of 2.0 years, 346 (2.7%) experienced a stroke (11.7 per 1000 patient-years). Figure 1 shows cumulative incidence function plots for stroke according to the tertile of risk score in 12,331 patients whose risk score can be calculated. The number of strokes in tertile 1, 2 and 3 were 80, 102 and 149, respectively. The 3-year cumulative incidence function rates of stroke were 2.0 (95% CI: 1.5–2.5) % in tertile 1, 2.6 (95% CI: 2.1–3.2) % in tertile 2, and 4.3 (95% CI: 3.6–5.2) % in tertile 3, respectively. In patients with tertile 3, the stroke rate was 18.1 per 1000 patient-years (compared to 20.1 per 1000 patient-years in patients with AF not receiving anticoagulation). In the Cox model, risk for stroke increased according to the elevation in the risk score (tertile 2: HR 1.47 (95% CI 1.09–1.97), tertile 3: HR 2.53 (95% CI 1.92–3.33), with tertile 1 as reference). Figure 2 shows calibration plots by comparing observed and predicted probabilities of stroke at 1 to 3 years. Discrimination evaluated using the overall c-index 0.84 (95% CI: 0.75–0.91) was good.

Conclusions

These findings validate a previously described predictive model and confirm that it is possible to identify a subset of HFrEF patients without AF who have a risk of stroke that approximates to that in patients with AF. In these patients, the risk/benefit balance might justify the use of prophylactic anticoagulation, but this hypothesis needs to be tested prospectively.

Funding Acknowledgement

Type of funding sources: Foundation.

Prognostic implications of NYHA class and NT-proBNP levels in mild heart failure: a PARADIGM-HF analysis

Background

Treatment recommendations for heart failure (HF) with reduced ejection fraction are primarily centered on New York Heart Association (NYHA) classification, such that apparently asymptomatic patients might not be eligible for disease-modifying therapies. NYHA classification, however, may be particularly limited to discriminate mild forms of HF.

Purpose

The present study aimed to determine the relationship between NYHA classification and an objective measure of HF severity (N-terminal pro–B-type natriuretic peptide [NT pro-BNP]), and their association with long-term prognosis in the PARADIGM-HF trial.

Methods

We compared PARADIGM-HF patients classified as NYHA class I, II, and III at randomization (NYHA class IV patients or with unavailable NYHA class were excluded [n=73]). We present kernel density estimation (KDE) plots–a non-parametric way to describe the underlying distribution of a variable–to compare NT-proBNP levels across NYHA classes. Logistic regression and the area under the receiver operating characteristic curve (AUC) were used to assess the ability to predict a patient's NYHA class using NT-proBNP levels. Time-to-event data were calculated with Kaplan–Meier estimates and NYHA class were further stratified by median baseline NT-proBNP (< or ≥1600 pg/ml). The primary outcome was cardiovascular death or first HF hospitalization.

Results

8326 patients were included in this analysis (median age, 64 years; women, 22%; and median left ventricular ejection fraction, 30%). Of 389 patients classified as NYHA class I at randomization, 228 (59%) changed functional class during the first year after randomization. For log-transformed NT-proBNP, KDE overlapped substantially across NYHA classes (Figure 1A). NT-proBNP levels were a poor predictor of NYHA classification: for NYHA class I vs. II, AUC (95% confidence interval [CI]) was 0.51 (0.48–0.54); for NHYA I vs. III, 0.57 (0.54–0.60); and for NYHA II vs. III, 0.56 (0.54–0.57). NYHA class III patients displayed a distinctively higher rate of cardiovascular deaths or first HF hospitalizations (Figure 1B). NYHA class I and II patients revealed lower event rates that were not significantly different (NYHA II vs. I, HR 1.24 [0.97–1.58]). Stratification by NT-proBNP levels identified subgroups with distinctive risk, such that NYHA I patients with high NT-proBNP levels (n=175) had a higher event rate than patients with low NT-proBNP with any NYHA class (Figure 1C).

Conclusion

NYHA class I and II patients overlapped substantially in objective HF measures and long-term prognosis. NYHA classification remains a powerful predictor of cardiovascular events but might be limited to differentiate mild forms of HF, as apparently asymptomatic patients based on physician-defined functional class might become symptomatic within a year and conceal subjects at substantial risk for adverse outcomes.

Funding Acknowledgement

Type of funding sources: None.

Prevalent and incident anaemia in PARADIGM-HF and effect of sacubitril/valsartan

Background

Anaemia is common in patients with HFrEF and is associated with poor clinical outcomes. Although they reduce rates of mortality and heart failure hospitalization, renin-angiotensin (RAS) blockers lower haemoglobin and may induce anaemia. Concomitant neprilysin inhibition might ameliorate this effect of RAS blockers.

Purpose

We investigated the effect of sacubitril/valsartan compared with enalapril on clinical outcomes, according to anaemia status, and on haemoglobin levels in PARADIGM-HF.

Methods

Patient characteristics and clinical outcomes were compared between patients with and without anaemia (defined as haemoglobin <120 g/L in women and <130 g/L in men) at baseline. We investigated the effect of randomized treatment (sacubitril/valsartan or enalapril) on clinical outcomes according to anaemia status at screening. We also examined the effect of treatment on change in haemoglobin from baseline and on the incidence of anaemia. The primary endpoint in PARADIGM-HF was the composite of heart failure hospitalization or cardiovascular death.

Results

Of 8239 participants with a baseline haemoglobin measurement, 1677 (20.4%) were anaemic. Compared to those without anaemia, patients with anaemia had a more severe heart failure profile, worse kidney function, greater neurohormonal derangement and worse clinical outcomes. Sacubitril/valsartan, compared to enalapril, reduced the risk of the primary endpoint similarly in patients with anaemia (HR 0.84, 95% CI 0.71–1.00) and without anaemia (HR 0.78, 95% CI 0.71–0.87), p-value for interaction=0.478. Between baseline and 12 months, haemoglobin decreased by 1.5 (95% CI 1.7 to 1.2) g/L with sacubitril/valsartan compared with 2.3 (2.6 to 2.0) g/L with enalapril group: mean difference 0.8 (95% CI 0.5 to 1.2) g/L, p<0.001. The between-treatment difference apparent by 12 months, persisted up to 36 months. Patients assigned to sacubitril/valsartan were less likely to develop new anaemia at 12 months [321 of 2806 (11.4%)] compared to patients randomized to enalapril [440 of 2384 (15.6%)], odds ratio 0.70 (95% CI 0.60–0.81), p<0.001.

Conclusions

Compared to enalapril, sacubitril/valsartan reduced mortality and hospitalization in HFrEF patients with and without anaemia. Haemoglobin decreased less with sacubitril/valsartan and the incidence of new anaemia was lower in the sacubitril/valsartan group compared with the enalapril group.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): PARADIGM-HF was funded by Novartis.

Implications of the 2021 CKD-EPI cystatin C/creatinine eGFR equation for eligibility for therapy in HFrEF: insights from PARADIGM-HF

Background

Estimated glomerular filtration rate (eGFR) is a key determinant of eligibility for many life-saving therapies in HFrEF. Recently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) provided new equations based on creatinine (CKD-EPIcr), cystatin C (CKD-EPIcys) or both (CKD-EPIcyscr) that do not include race. These new equations may reclassify individuals, irrespective of race, from one eGFR category to another, with implications for eligibility for HFrEF treatments.

Purpose

To assess the difference between eGFR estimation using the 2021 CKD-EPIcyscr equation and the 2009 CKD-EPIcr and Modification of Diet in Renal Disease Study (MDRD)-4 equations which are still standard in many European laboratories.

Methods

We included patients from PARADIGM-HF with cystatin C and creatinine values available at the time of randomization. For each patient, baseline eGFRs were calculated using the 3 equations described. Our focus was on patients with chronic kidney disease (CKD) stages III–V.

Results

Overall, 1910 patients were eligible. Mean age was 67.3 (10.1) year and 385 (18.7%) were female. Using 2009 CKD-EPIcr, 779 patients were in CKD stages 3–5, of which 233 (30%) were reclassified to a better CKD stage (higher eGFR) with the 2021 CKD-EPIcyscr equation (Table 1). Similar reclassification was seen when comparing MDRD-4 with the 2021 CKD-EPIcyscr equation: 277 (33%) of 831 patients in CKD stages 3–5 were reclassified to a better CKD stage (Figure 1).

Conclusions

The 2021 CKD-EPIcyscr equation favourably reclassified CKD stage in a large percentage of patients with HFrEF and a low eGFR, potentially increasing the proportion of these patients considered eligible for guideline-recommended therapies.

Funding Acknowledgement

Type of funding sources: None.

P6350Impact of diabetes on serum biomarkers in heart failure with preserved ejection fraction: insights from the spironolactone for heart failure with preserved ejection fraction (TOPCAT) trial

Background and purpose

Diabetes mellitus (DM) is common in heart failure with preserved ejection fraction (HFpEF). Patients with DM and HF with reduced ejection fraction have higher levels of prognostic biomarkers relative to non-diabetics. We sought to examine differences in biomarkers at baseline and over time in patients with HFpEF with and without DM (non-DM).

Methods

The Americas cohort of the TOPCAT trial included 248 subjects with baseline measurements of serum biomarkers and follow-up measures 12 months later. Subjects were identified as non-DM or DM at baseline. Baseline values were compared using non-parametric tests and 12-month changes were compared via linear regression after log-transformation and adjustment for baseline biomarker value, age, gender, randomization strata, and randomized treatment.

Results

At baseline, DM patients had significantly lower eGFR and higher hsCRP, PIIINP, TIMP1, and Gal-3 levels versus non-DM patients (Table). In addition, there was a significantly larger increase over time in levels of hs-TnT, a marker of myocyte death, in DM vs. non-DM patients (p=0.016).

Baseline and 12-Month Biomarkers Baseline % Change at 12 Months Non-DM (n=132) DM (n=116) p Non-DM (n=110) DM (n=94) p eGFR (mL/min/1.73m2) 67 [57, 77] 57 [46, 73] 0.003 −14% (−17, −10) −14% (−18, −10) 0.34 hsCRP (mg/L) 2.4 [1.1, 5.6] 3.1 [1.6, 7.5] 0.046 1% (−5, 3) −11% (−27, 7) 0.54 NT-proBNP (pg/mL) 624 [338, 1235] 629 [278, 1429] 0.80 −2% (−12, 10) −5% (−21, 13) 0.48 hs-TNT (ng/mL) 5.7 [3.1, 12.4] 7.1 [3.7, 14.2] 0.17 −1% (−14, 13) 11% (−3, 27) 0.016 Soluble ST2 (ng/mL) 28 [22, 32] 28 [21, 35] 0.36 −1% (−7, 5) −4% (−9, 2) 0.60 Aldosterone (ng/L) 149 [120, 202] 142 [113, 174] 0.09 17% (9, 26) 23% (14, 33) 0.76 PICP (ng/mL) 137 [101, 169] 127 [102, 155] 0.29 5% (−5, 17) 1% (−9, 12) 0.07 CITP (ng/mL) 1.6 [1.0, 2.8] 1.6 [0.9, 3.0] 0.93 −25% (−37, 10) −23% (−36, −8) 0.87 PIIINP (ng/mL) 23 [16, 30] 28 [21, 36] <0.001 5% (−4, 15) 5% (−3, 14) 0.12 TIMP-1 (ng/mL) 188 [170, 212] 212 [183, 245] <0.001 −1% (−4, 2) −2% (−5, 2) 0.59 Galectin-3 (ng/mL) 20 [16, 23] 22 [18, 28] <0.001 6% (3, 10) 9% (4, 14) 0.52 eGFR, estimated glomerular filtration rate; hsCRP, high-sensitivity CRP; NT-proBNP, N-terminal pro-B-type natriuretic peptide; hs-TnT, high-sensitivity troponin T; PICP, pro-collagen type I carboxy-terminal peptide; CITP, collage type I; PIIINP=pro-collagen type III amino-terminal peptide; TIMP-1=tissue inhibitor of MMP-1.

Conclusions

In comparison to patients without DM, those with DM had poorer renal function and higher baseline levels of markers of myocardial stretch, myocyte death, and pro-fibrotic biomarkers. Further, hs-TnT increased over 12 months only in patients with DM.

Is a reduction in albuminuria associated with renal and cardiovascular protection? A post hoc analysis of the ALTITUDE trial

AIMS

To investigate whether the degree of albuminuria reduction observed in the ALTITUDE trial is associated with renal and cardiovascular protection, and secondly, whether the reduction in albuminuria was too small to afford clinical benefit.

METHODS

In a post hoc analysis of the ALTITUDE trial in 8561 patients with type 2 diabetes and chronic kidney disease or cardiovascular disease we examined the effect of albuminuria changes at 6 months on renal and cardiovascular outcomes using Cox proportional hazard regression.

RESULTS

The median change in albuminuria in the first 6 months in the aliskiren arm of the trial was -12% (25th to 75th percentile: -48.7_to_ +41.9%) and 0.0% (25th to 75th percentile: -40.2_to_55%) in the placebo arm. Changes in albuminuria in the first 6 months were linearly associated with renal and cardiovascular endpoints: a >30% reduction in albuminuria in the first 6 months was associated with a 62% reduction in renal risk and a 25% reduction in cardiovascular risk compared with an increase in albuminuria. The association between changes at 6 months in albuminuria and renal or cardiovascular endpoints was similar in the two treatment groups (p for interaction >0.1 for both endpoints).

CONCLUSIONS

The addition of aliskiren to angiotensin-converting enzyme inhibitor/angiotensin receptor blocker therapy resulted in albuminuria changes that were associated with renal and cardiovascular risk changes. This did not translate into renal or cardiovascular protection because the overall reduction in albuminuria in the aliskiren arm was too small and nearly similar to that in the placebo arm.

T and Tk antigen activation in necrotising enterocolitis: manifestations, severity of illness, and effectiveness of testing

AIMS

To determine if T or Tk antigen activation is associated with different and more severe manifestations of illness in infants with necrotising enterocolitis (NEC); and if a policy of testing infants with suspected sepsis or NEC for T and Tk antigen activation is effective.

METHODS

A case-control study of infants with confirmed NEC, born after the introduction of screening, was undertaken:17 activated infants were compared with 28 non-activated controls, matched for gestation and weight. A historical control study compared the outcome of infants before and after the introduction of testing.

RESULTS

Of 201 infants with confirmed NEC, 27 were T or Tk antigen activated-10 (9%) before and 17 (19%) after the introduction of testing. T or Tk antigen activated infants had a significantly higher mortality (35% vs 7%); more frequent (71% vs 21%) and severe haemolysis, hyperkalaemia, renal impairment, acidosis; and they received more colloid for resuscitation. While only known activated infants in both time periods were managed with the use of low titre T antibody blood products, there was a significant increase in mortality (odds ratios 2.6; 95% CI 1.2, 5.6) and incidence of surgery (OR 2.7; 1.5, 4.9) after the introduction of testing. The increased mortality (OR 2.6; 0.8, 5.2) and incidence of surgery (OR 1.8; 0.9, 3.7) were no longer significant after adjustment for several perinatal risk factors.

CONCLUSIONS

In a retrospective case-control study, routine testing of at risk infants increased the detection rate of T and Tk antigen activation. The use of low titre T plasma products in these patients did not reduce mortality compared with historical controls. A randomised controlled trial of testing in at risk infants, or of the use of low titre T plasma products in babies with NEC and T activation, is warranted.

Persistence of Japanese encephalitis virus in the human nervous system

Immunological and virological evidence for persistence of Japanese encephalitis virus (JEV) in the human nervous system is described in 16/323 (5%) laboratory-confirmed cases of Japanese encephalitis. In 9/16 patients, JEV specific IgM antibodies were detected in the CSF even at 50-180 days after the onset of symptoms. Similarly, in 7/16 patients, apart from IgM antibodies, viral antigen was also present in the CSF beyond the third week of illness and in one patient it could be detected even at 117 days. Infectious virus could be isolated from the CSF beyond the third week of illness in 3/16 patients. In one patient, JEV was isolated from the CSF on three consecutive occasions at 90, 110, and 117 days after onset of clinical symptoms. These findings suggest that JEV persists in the nervous system of a small proportion of patients.