POS0315 LONG-TERM SAFETY AND EFFICACY OF LENABASUM DURING 3 YEARS IN AN OPEN-LABEL EXTENSION (OLE) OF A PHASE 2 STUDY OF LENABASUM IN REFRACTORY SKIN DISEASE IN DERMATOMYOSITIS (DM)

Background:

Lenabasum is a synthetic, non-immunosuppressive, selective cannabinoid receptor type 2 agonist that activates resolution of inflammation. Lenabasum had acceptable safety and tolerability and improved efficacy outcomes in the initial 16-week double-blinded, randomized, placebo-controlled Part A of Phase 2 trial JBT101-DM-001 (NCT02466243) in DM subjects with refractory skin involvement. In that study, lenabasum or placebo was added to stable background treatment, with immunosuppressive therapies allowed.

Objectives:

To assess long-term safety and efficacy in DM subjects in this study.

Methods:

Subjects who completed Part A of the Phase 2 study (n = 22) were eligible to receive oral lenabasum 20 mg BID in an open-label extension (OLE) that assessed safety and efficacy at 4 weeks, then every 8 weeks.

Results:

20/22 (91%) eligible subjects enrolled in the OLE, following a mean interval of 31 weeks from the end of Part A, during which they continued to receive standard-of care treatments, to the start of the OLE during which lenabasum 20 mg BID was added. 17/20 (85%) subjects were on stable baseline immunosuppressive drugs. At the time of this data cut-off, 17 subjects were still enrolled, 17 had completed 140 months (2.7 years), and 15 had completed 156 months (3 years) of OLE dosing.

All OLE subjects experienced at least 1 adverse event (AE), with 118 AEs during the OLE through Dec 2020. Most AEs were mild (n = 111, 94%), with 2 severe AEs (fatigue and metastatic prostate cancer) considered unrelated to lenabasum. AEs occurring in ≥ 3/20 OLE subjects were: URI (n = 5); fatigue (n = 4); nausea (n = 3); common cold (n = 3); UTI (n = 3); and DM flare (n = 3). No serious AEs related to lenabasum have been reported in this OLE to date. No subject discontinued the OLE because of an AE related to lenabasum.

Improvement was seen in multiple physician- and patient-reported efficacy outcomes. CDASI activity score improved through the first 15 months of lenabasum treatment in the OLE and remained stable thereafter, with an improvement of ~20 points from the beginning of the study maintained from Month 15 through Year 3 in the OLE. CDASI damage score increased through the first year of the OLE, even though skin activity was decreasing, but lessened thereafter, returning after 3 years to about the same level it was at the beginning of the OLE. Other outcomes shown in Figure 1 followed the same general pattern as CDASI activity score, with improvement through the first 12-16 months of the OLE, then stability thereafter. Of note, 2 subjects had disease flares shortly after stopping lenabasum for conclusion of the OLE.

Conclusion:

Lenabasum continues to have a favorable safety and tolerability profile in the OLE of the Phase 2 trial JBT101-DM-001 with no serious AEs or study discontinuations related to lenabasum. The CDASI activity score and multiple other physician and patient-reported outcomes improved and have remained stable, showing durability of improvement in these patients with refractory skin disease. Skin damage was reversible and began to improve once skin activity stabilized. The limitations of attributing this improvement to lenabasum in the setting of open-label dosing is acknowledged. These data support further testing of lenabasum for the treatment of DM, and a Phase 3 study of lenabasum in DM is ongoing.

Figure 1.

Change from Baseline in Selected Efficacy Outcomes in OLE of Phase 2 Trial JBT101-DM-001

Disclosure of Interests:

Victoria Werth Grant/research support from: Investigator for Corbus Pharmaceuticals and received funding to conduct trials, Josef Concha: None declared, Julie Burroughs: None declared, Joyce Okawa: None declared, Rui Feng: None declared, Anisha Jobanputra: None declared, Robert Borucki: None declared, Kathleen Hally Employee of: Employee of Corbus Pharmaceuticals, Emily Hejazi: None declared, Michael Tillinger Employee of: Employee of Corbus Pharmaceuticals, Scott Constantine Employee of: Employee of Corbus Pharmaceuticals, Nancy Dgetluck Employee of: Employee of Corbus Pharmaceuticals, Barbara White Employee of: Employee and stockholder of Corbus Pharmaceuticals

Evaluation of the reliability and validity of the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) in paediatric cutaneous lupus among paediatric dermatologists and rheumatologists

BACKGROUND

The Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) is a reliable outcome measure for cutaneous lupus erythematosus (CLE) in adults used in clinical trials. However, it has not been validated in children, limiting clinical trials for paediatric CLE.

OBJECTIVES

This study aimed to validate the CLASI in paediatrics.

METHODS

Eleven paediatric patients with CLE, six dermatologists and six rheumatologists participated. The physicians were trained to use the CLASI and Physician's Global Assessment (PGA), and individually rated all patients using both tools. Each physician reassessed two randomly selected patients. Within each physician group, the intraclass correlation coefficient (ICC) was calculated to assess the reliability of each measure.

RESULTS

CLASI activity scores demonstrated excellent inter- and intrarater reliability (ICC > 0·90), while the PGA activity scores had good inter-rater reliability (ICC 0·73-0·77) among both specialties. PGA activity scores showed excellent (ICC 0·89) and good intrarater reliability (ICC 0·76) for dermatologists and rheumatologists, respectively. Limitations of this study include the small sample size of patients and potential recall bias during the physician rerating session.

CONCLUSIONS

CLASI activity measurement showed excellent inter- and intrarater reliability in paediatric CLE and superiority over the PGA. These results demonstrate that the CLASI is a reliable and valid outcome instrument for paediatric CLE.

Evaluation of the reliability of the Cutaneous Dermatomyositis Disease Area and Severity Index and the Cutaneous Assessment Tool-Binary Method in juvenile dermatomyositis among paediatric dermatologists, rheumatologists and neurologists

BACKGROUND

The Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) and Cutaneous Assessment Tool-Binary Method (CAT-BM) have been shown to be reliable and valid outcome measures to assess cutaneous disease in adult dermatomyositis (DM) and juvenile DM (JDM), respectively.

OBJECTIVES

This study compared the CDASI and CAT-BM for use by paediatric dermatologists, paediatric rheumatologists and paediatric neurologists in patients with JDM.

METHODS

Five paediatric dermatologists, five paediatric rheumatologists and five paediatric neurologists each evaluated 14 patients with JDM using the CDASI, CAT-BM, and skin Physician Global Assessment (PGA) scales. Inter-rater reliability, intra-rater reliability, construct validity and completion time were compared.

RESULTS

Inter-rater reliability for CDASI activity and damage scores was good to moderate for paediatric dermatologists and rheumatologists, but poor for paediatric neurologists. The inter-rater reliability for CAT-BM activity scores was moderate for paediatric dermatologists and rheumatologists, but poor for paediatric neurologists and poor across all specialties for damage scores. Intra-rater reliability for the CDASI and CAT-BM activity and damage scores was moderate to excellent for paediatric dermatologists, rheumatologists and neurologists. Strong associations were found between skin PGA activity and damage scores and CDASI or CAT-BM activity and damage scores, respectively (P < 0·002). The CDASI had a mean completion time of 5·4 min compared with that for the CAT-BM of 3·1 min.

CONCLUSIONS

Our data confirm the reliability of the CDASI activity and damage scores and the CAT-BM activity scores when used by paediatric dermatologists and rheumatologists in assessing JDM. Significant variation existed in the paediatric neurologists' scores.

The systemic management of cutaneous dermatomyositis: Results of a stepwise strategy

Treatment of dermatomyositis (DM) is often achieved with a stepwise algorithm. However, the literature lacks quality evidence to support the use of this therapeutic strategy. The result of a stepwise therapeutic strategy in the management of skin-only DM is presented to better understand the clinical outcomes and allow for future studies. A cohort of 102 patients with DM, 41 of whom had skin-only disease, were seen between July 2009 and April 2013 at a referral-based connective tissue disease clinic. The Cutaneous Dermatomyositis Disease Area and Severity Index was used to prospectively assess disease severity and the outcomes in 41 adult patients with skin-only DM were analyzed. Of the 41 patients with skin-only DM, 23 patients (56.1%) received antimalarial medications alone and 18 patients (43.9%) received second- or third-line agents. Ten patients (24.4%) remained at the first level of the treatment algorithm and received only hydroxychloroquine. Prednisone was included in the treatment regimen for 11 patients with skin-only disease (26.8%). The results show that management of cutaneous DM often requires second-line agents because antimalarial medications alone are insufficient to treat most patients with skin-only disease.

The reliability of the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) among dermatologists, rheumatologists and neurologists

BACKGROUND

Previous studies have shown that skin disease in dermatomyositis (DM) is best assessed using the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI). Although the CDASI has been validated for use by dermatologists, it has not been validated for use by other physicians such as rheumatologists and neurologists, who also manage patients with DM and assess skin activity in clinical trials.

OBJECTIVES

To assess the reliability of the CDASI among dermatologists, rheumatologists and neurologists.

METHODS

Fifteen patients with cutaneous DM were assessed using the CDASI and the Physician Global Assessment (PGA) by five dermatologists, five rheumatologists and five neurologists.

RESULTS

The mean CDASI activity scores for dermatologists, rheumatologists and neurologists were 21·0, 21·8 and 20·8, respectively. These mean scores were not different among the specialists. The CDASI damage score means for dermatologists, rheumatologists and neurologists were 5·3, 7·0 and 4·8, respectively. The mean scores between dermatologists and rheumatologists were significantly different, but the means between dermatologists and neurologists were not. The intraclass correlation coefficients (ICCs) for interrater reliability for CDASI activity and damage were good to excellent for dermatologists and rheumatologists, and moderate to excellent for neurologists. The ICCs for intrarater reliability for CDASI activity and damage were excellent for dermatologists and rheumatologists and moderate to excellent for neurologists. The PGA displayed lower interrater and intrarater reliability relative to the CDASI.

CONCLUSIONS

Our results confirm the reliability of the CDASI when used by dermatologists and rheumatologists. The data for its use by neurologists were not as robust.

Validation of the Cutaneous Dermatomyositis Disease Area and Severity Index: characterizing disease severity and assessing responsiveness to clinical change

BACKGROUND

The Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) was developed for use in clinical trials and longitudinal patient assessment.

OBJECTIVES

To characterize disease severity using the CDASI and assess the responsiveness of this instrument to clinically meaningful changes in disease activity.

METHODS

Patients with cutaneous dermatomyositis at the University of Pennsylvania (UPenn, n = 93) and Stanford University (Stanford, n = 106) were prospectively evaluated using the CDASI, physician global assessment (PGA) Likert scales and a visual analogue scale (VAS). Data was analysed using logistic regression models and receiver operating characteristic curves to select cut-offs.

RESULTS

Baseline CDASI activity scores for the patients evaluated at UPenn ranged from 0 to 47 (median 17), and baseline PGA VAS scores ranged from 0 to 9·6 (median 1·1). At UPenn a CDASI activity score of 19 differentiated mild from moderate and severe disease. At Stanford baseline CDASI scores ranged from 0 to 48 (median 21), baseline PGA VAS scores ranged from 0 to 9·7 (median 4·2) and CDASI activity scores of 14 or less characterized mild disease. When a 2-cm change in the PGA VAS was regarded as a clinically significant improvement, a 4-point (UPenn) or 5-point (Stanford) change in CDASI reflected a minimal clinically significant response.

CONCLUSIONS

The CDASI is a valid and responsive measure that can be used to characterize cutaneous dermatomyositis severity and detect improvement in disease activity. Variations in cut-offs may be due to differences in disease severity between the two populations or inter-rater variations in the use of the external gold measures.

A multicentre randomized trial of the treatment of patients with pemphigus vulgaris with infliximab and prednisone compared with prednisone alone

BACKGROUND

Pemphigus vulgaris (PV) is a blistering disease and tumour necrosis factor-α has a role in its pathogenesis.

OBJECTIVES

To evaluate the safety of infliximab (IFX) with prednisone compared with prednisone alone in the treatment of PV. In addition, treatment response was assessed and mechanistic studies were performed.

METHODS

Subjects with PV who had ongoing disease activity while being maintained on prednisone were randomized to receive either IFX or placebo in addition to prednisone. Response status and immunoglobulin (Ig) G anti-desmoglein (Dsg)1 and Dsg3 antibodies were assessed at 18 and 26 weeks.

RESULTS

Ten subjects were randomized to each group. There were no safety signals during the course of the study. At week 18, one subject in each group had responded. At week 26, three IFX-treated subjects vs. none in the placebo group had responded (P = 0·21). At weeks 18 and 26, the median IgG anti-Dsg1 and anti-Dsg3 levels were lower in the IFX-treated patients [IgG anti-Dsg-1 (week 18, P = 0·035; week 26, P = 0·022); IgG anti-Dsg3 (week 18, P = 0·035; week, 26 P = 0·05)].

CONCLUSIONS

This study is limited by the relatively small sample size. There was no significant difference between study arms in the proportion of subjects with treatment-related adverse events > grade 3. IFX therapy was not shown to be effective for the treatment of patients with PV in this randomized, placebo-controlled trial, although IFX treatment may be associated with a decrease in anti-Dsg1 and Dsg3 antibodies.

Improvement in the cutaneous disease activity of patients with dermatomyositis is associated with a better quality of life

BACKGROUND

Cutaneous dermatomyositis (DM) disease activity is associated with decreased quality of life.

OBJECTIVES

To assess if an improvement in quality of life, as measured by the Skindex-29 and patient-reported itch and pain on a 10-point visual analogue scale (VAS), correlated with an improvement in cutaneous DM disease activity.

METHODS

Patients with a completed cutaneous DM disease area and severity index [Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI)] at two visits separated by at least 2 months were classified into responder (n = 15) and nonresponder (n = 30) groups according to the point change in the CDASI activity scores between visits. Responders had at least a four-point improvement in CDASI activity, indicating clinically relevant improvement.

RESULTS

The change from baseline to the follow-up visit of the Skindex-29 subscale scores for the responders vs. the nonresponders were significantly different for emotions (P < 0·01), functioning (P < 0·01) and symptoms (P < 0·01). The change in VAS score between responders and nonresponders was also significant for itch (P = 0·01) and pain (P = 0·04). There was no significant difference between the groups in terms of disease subtype, sex, race, age, treatment for DM, smoking history or a history of malignancy within 5 years of a diagnosis of DM.

CONCLUSIONS

This is the first study to demonstrate that the quality of life of patients with DM improved as their cutaneous disease activity decreased.

The impact of skin damage due to cutaneous lupus on quality of life

BACKGROUND

Patients with more severe cutaneous lupus erythematosus (CLE) have a poorer quality of life (QoL). Racial and ethnic disparities have been reported in disease activity and outcomes in systemic lupus erythematosus, but similar information is not available for CLE.

OBJECTIVES

To evaluate the impact of lupus-related skin damage on skin-specific QoL, and to analyse differences stratified by ethnic background.

METHODS

Data collected included sex, race, diagnosis and Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) and Skindex-29 scores. These parameters were analysed at the initial and last visits. CLASI damage scores (dyspigmentation and scarring) and activity scores were collected, grouped by ethnicity, and correlated with Skindex-29. Overall, 223 patients were analysed at baseline, with 141 completing more than one study visit.

RESULTS

The majority of patients were white (63·7%), followed by African American (29·1%) and Asian American (4·0%). African American patients accounted for a disproportionate percentage of both localized (50%) and generalized discoid lupus erythematosus (DLE) (49%). Median CLASI damage scores differed significantly between the African American, white and Asian American patients, at both the first (8·5, 4·0, 7·0, respectively; P < 0·0001) and last visit (10·0, 6·0, 8·5, respectively; P < 0·01). CLASI damage scores in African Americans correlated with CLASI activity scores (Spearman r = 0·45, P = 0·0003).

CONCLUSIONS

There was no significant correlation between CLASI damage scores and Skindex domains overall. Individually, dyspigmentation and scarring also did not have a significant effect on QoL. Ethnic differences in patients with CLE were found: African American patients exhibited a high rate of DLE and experienced damage early in their disease course, frequently in conjunction with disease activity.

The interferon-regulated gene signature is elevated in subacute cutaneous lupus erythematosus and discoid lupus erythematosus and correlates with the cutaneous lupus area and severity index score

BACKGROUND

There is increased expression of type I interferon (IFN)-regulated proteins in the blood and target tissues of patients with cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE). Patients with SLE have increased IFN-regulated gene expression pointing towards a possible underlying genetic defect.

OBJECTIVES

To determine expression levels of five type I IFN-regulated genes that are highly expressed in SLE in the peripheral blood of patients with CLE and to correlate the expression levels with cutaneous disease activity.

METHODS

Peripheral blood was obtained from 10 healthy controls and 30 patients with CLE, including eight with concomitant SLE. Total RNA was extracted and reverse transcribed into complementary DNA. Gene expression levels were measured by real-time polymerase chain reaction. Gene expression was normalized to GAPDH, standardized to healthy controls and then summed to calculate an IFN score for each patient. Disease activity was assessed with the Cutaneous Lupus Area and Severity Index (CLASI).

RESULTS

Patients with subacute CLE (SCLE) and discoid lupus erythematosus (DLE) had elevated IFN scores compared with healthy controls regardless of concomitant SLE (P < 0·01 with SLE and P < 0·05 without SLE). There was no difference between patients with tumid lupus erythematosus (TLE) and healthy controls. The IFN score correlated with CLASI scores (Spearman's rho = 0·55, P = 0·0017).

CONCLUSIONS

Patients with SCLE and DLE have an IFN signature, as seen in SLE. The level of gene expression correlates with cutaneous disease activity. These findings support a shared pathogenesis between SLE and some subtypes of CLE.

Modification of the cutaneous dermatomyositis disease area and severity index, an outcome instrument

BACKGROUND

Validated outcome measures in dermatology help standardize and improve patient care. A scoring system of skin disease severity in dermatomyositis known as the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) has been developed.

OBJECTIVES

To simplify and improve the tool for clinical research and care, we modified the CDASI and validated the new version, v2.

METHODS

The original CDASI has four activity and two damage measures. The modified CDASI has three activity and two damage measures. The skin disease of 20 patients with dermatomyositis was evaluated by the same dermatologist using both the original and the modified CDASI. Global validation measures were implemented to assess overall skin disease state, skin disease activity and skin damage. Spearman's rho (r(sp)), adjusted for multiple observations on subjects, was used to determine the relationship between the two versions of the CDASI and their correlation with the physician global measures (PGMs).

RESULTS

The total score and activity and damage subscores of the original and the modified CDASI correlated perfectly with each other (r(sp) = 0.99, 1.00, 1.00). The PGM-overall skin scale correlated with the total scores (r(sp) = 0.72, r(sp) = 0.76) and activity subscores (r(sp) = 0.68, r(sp) = 0.63) but not with the damage subscores (r(sp) = 0.14, r(sp) = 0.15) of the original and the modified CDASI, respectively. However, the PGM-activity and PGM-damage scales correlated with the activity (r(sp) = 0.76, r(sp) = 0.75) and damage subscores (r(sp) = 0.90, r(sp) = 0.90), respectively, of the original and the modified CDASI.

CONCLUSIONS

The modified CDASI is perfectly correlated with the original CDASI. It has equally good concurrent validity with the PGM-overall skin and PGM-activity scales. The CDASI subscores have equally good concurrent validity with the PGM-activity and PGM-damage scales. We suggest that PGMs of skin disease activity and damage should be assessed separately for greater specificity. The modified CDASI is a refined and equally as useful outcome measure.

Comparison of the reliability and validity of outcome instruments for cutaneous dermatomyositis

BACKGROUND

Reliable and validated measures of skin disease severity are needed for cutaneous dermatomyositis (DM). Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI), Dermatomyositis Skin Severity Index (DSSI) and Cutaneous Assessment Tool (CAT) skin indices have been developed as outcome instruments.

OBJECTIVES

We sought to demonstrate reliability and validity of the CDASI, and to compare the CDASI with other potential tools for use in measuring disease severity in cutaneous dermatomyositis.

PATIENTS AND METHODS

CDASI has four activity and two damage measures, with scores from 0 to 148. DSSI assesses activity based on body surface area and severity on a scale of 0-72. CAT uses 21 activity and damage items, for a range of 0-175 for activity and 0-33 for damage. Ten dermatologists used the instruments to score the same 12-16 patients in one session. Global validation measures were administered to physicians and patients.

RESULTS

Global validation measures correlated with the three outcome instruments (P < 0.0001). CAT displayed lower inter- and intrarater reliability relative to the CDASI. All scales correlate better with physician than patient global skin measures.

CONCLUSIONS

It appears that the CDASI may be a useful outcome measure for studies of cutaneous DM. Further testing to compare responsiveness of all three measures is necessary.

The Cutaneous Lupus Erythematosus Disease Activity and Severity Index: expansion for rheumatology and dermatology

OBJECTIVE

To evaluate the validity of the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) for use by rheumatologists via reliability testing, and to extend the validation for dermatologists.

METHODS

Fourteen subjects with cutaneous lupus erythematosus (CLE; n = 10), a mimicker skin disease only (a cutaneous lesion that may appear clinically similar to CLE; n = 1), or both (n = 3) were rated with the CLASI by academic-based dermatologists (n = 5) and rheumatologists (n = 5).

RESULTS

The dermatology intraclass correlation coefficient (ICC) was 0.92 for activity and 0.82 for damage; for rheumatology the ICC was 0.83 for activity and 0.86 for damage. For intrarater reliability, the dermatology Spearman's rho was 0.94 for activity and 0.97 for damage; for rheumatology the Spearman's rho was 0.91 for activity and 0.99 for damage.

CONCLUSION

Our data confirm the reliability of the CLASI when used by dermatologists and support the CLASI as a reliable instrument for use by rheumatologists.

Caudate blood flow and volume are reduced in HIV+ neurocognitively impaired patients

OBJECTIVE

To evaluate the effects of HIV-associated neurocognitive impairment on caudate blood flow and volume.

METHODS

The authors performed continuous arterial spin labeled MRI on 42 HIV+ patients (23 subsyndromic and 19 HIV neurosymptomatic) on highly active antiretroviral therapy and 17 seronegative controls. They compared caudate blood flow and volume among groups.

RESULTS

A stepwise decrease in both caudate blood flow and volume was observed with increasing HIV-associated neurocognitive impairment. Compared with seronegative controls, baseline caudate blood flow was reduced in HIV+ neurosymptomatic patients (p = 0.001) with a similar decreasing trend for subsyndromic HIV+ patients (p = 0.070). Differences in caudate volume were observed only for neurosymptomatic HIV+ patients compared with controls (p = 0.010). A Jonckheere-Terpstra test for trends was significant for both caudate blood flow and volume for each of the three subgroups. Pearson product moment correlation coefficients were not significant between caudate blood flow and volume for each group.

CONCLUSIONS

Decreasing trends in caudate blood flow and volume were associated with significantly increasing HIV-associated neurocognitive impairment (HNCI), with the greatest decreases observed for more severely impaired patients. However, reductions in caudate blood flow and volume were poorly correlated. Changes in residual caudate blood flow may act as a surrogate biomarker for classifying the degree of HNCI.

Prognostic significance of circulating matrix metalloproteinase-2 to tissue inhibitor of metalloproteinases-2 ratio in recurrence of urothelial cancer after complete resection

The relationship between the serum matrix metalloproteinase-2 (MMP-2):tissue inhibitor of metalloproteinases-2 (TIMP-2) ratio and disease recurrence was examined in 53 urothelial cancer patients with muscular invasion or with lymph node metastasis who underwent complete resection. The mean MMP-2:TIMP-2 ratio in 31 patients with recurrence was significantly higher than that in 22 patients without recurrence (P < 0.05). Disease-free survival of patients with high MMP-2:TIMP-2 ratios was extremely poor compared with that of patients with lower ratios (P < 0.01). Cox's multivariate analysis suggests that the serum MMP-2:TIMP-2 ratio would be a new independent prognostic indicator of urothelial cancer recurrence.

[A case report on a double chambered right ventricle (DCRV)--pre- and postoperative responses of the right ventricle to atrial pacing and the isoproterenol tolerance test]

To evaluate the development of an anomalous muscle bandle of the right ventricle (RV) and results of surgical intervention, responses of the RV to atrial pacing and the isoproterenol tests were examined in both the pre- and postoperative periods. Although cardiac output did not increase in proportion to the rate of atrial pacing or the dose of isoproterenol, the pressure gradient through the RV increased abnormally from 38 mmHg to 59 mmHg (atrial pacing) and 116 mmHg (isoproterenol). On the other hand, postoperative evaluation showed normal RV responses in these tests. Since the response of the right ventricle to these tolerance tests in patients with DCRV in pre- and postoperative periods has not been well elucidated, a precise evaluation is reported in this paper.