Pharmacological counseling in hepatotoxicity induced by macitentan and selexipag: a case report

Background

Pulmonary arterial hypertension is a progressive, debilitating condition characterized by increased resistance in the pulmonary arterial circulation. Current treatments for pulmonary arterial hypertension include endothelin receptor antagonists such as bosentan, sitaxentan, ambrisentan, macitentan, and oral prostacyclin receptor agonists such as selexipag. Endothelin receptor antagonists have been associated with liver injury, while hepatotoxicity was not reported for selexipag. Although genetic variability has been indisputably associated with variability in drug response, no study has been designed until now to assess its effects on the pharmacokinetics of endothelin receptor antagonists or selexipag.

Case presentation

We report the case of a 58-year-old female Caucasian patient with a dramatic increase in plasma levels of transaminases after treatment with macitentan and selexipag, drugs whose risk of causing liver injury has so far been considered limited. After therapy discontinuation, plasma levels of transaminases returned to baseline, thus suggesting a role of these drugs in the observed hepatotoxicity. After pharmacological counseling, we decided to introduce ambrisentan for the patient’s treatment. After 7 months of treatment, no liver injury has been reported. To evaluate the role of genetic factors in the observed hepatotoxicity, we genotyped the patient for single-nucleotide polymorphisms previously associated with macitentan, ambrisentan, or selexipag metabolism. We found a genetic profile associated with a poor metabolizer (PM) phenotype for CYP2C8 and CYP2C9, key enzymes for elimination of both macitentan and selexipag. The reported results suggest that an allelic profile associated with low activity for CYP2C8 and CYP2C9 enzyme could be a potential risk factor for macitentan and selexipag-induced liver injury and could provide a possible marker for early identification of subjects at higher risk of developing hepatotoxicity.

Conclusions

A multidisciplinary approach based on clinical evaluation, as well as pharmacological counseling and evaluation of the patient’s genetic profile, might be useful for identification of patients with a high chance of drug-induced liver injury, avoiding unnecessary risks in therapy selection and prescription.

380 Left heart disease phenotype and use of pulmonary vasodilators in elderly patients with pulmonary arterial hypertension: the Patriarca registry

Aims

The prevalence of occult left heart disease (LHD) and the feasibility of vasodilator therapy in the progressively growing population of elderly subjects with pulmonary arterial hypertension (PAH) are under scrutiny. We evaluated the presence of a LHD phenotype and the patterns of vasodilator treatment in such patients.

Methods and results

The PATRIARCA registry collected cross-sectional data from 180 subjects with PAH or chronic thromboembolic pulmonary hypertension and ≥70 years of age in 11 Italian centres between 1 December 2019 and 15 September 2020. After excluding patients with CTEPH or incomplete follow-up haemodynamic parameters, 77 individuals with PAH diagnosed at ≥ 65 years of age according to current guidelines were included in the analysis. A LHD phenotype was defined as follows, expanding the criteria adopted in the AMBITION trial: (i) ≥3 among body mass index ≥30 kg/m2, systemic hypertension, diabetes, and significant coronary artery disease; (ii) 2 of the risk factors for LHD above and ≥1 among permanent atrial fibrillation, left ventricular (LV) hypertrophy, LV ejection fraction <50%, at least moderate mitral or aortic valve disease, and left atrial dilation; (iii) pulmonary vascular resistance (PVR) between 3 and 3.75 WU or PVR between 3.75 and 6.25 WU in the presence of a pulmonary artery wedge pressure (PAWP) of 13–15 mmHg. Forty-one (53%) patients had a LHD phenotype according to the most recent clinical and haemodynamic evaluation, which was performed 16 (4–35) months after diagnosis (Figure). As per definition, they had higher rates of comorbidities and more often echocardiographic signs of LHD (not shown). The frequency of NYHA classes I–II was comparable between the two groups, while the 6 min-walking distance tended to be lower in subjects with a LHD phenotype than in those without (Figure, left panel). Furthermore, these latter had lower PVR and higher PAWP. No differences were seen in treatment with pulmonary vasodilators, with around 50% of patients receiving double oral combination therapy in both groups (Figure, right panel). During the study period, 7 (17%) and 4 (11%) patients died in the LHD and no-LHD groups, respectively (P = 0.40).

Conclusions

In this real-world cohort of elderly patients, a LHD phenotype was common despite an initial haemodynamic diagnosis of PAH. However, it did not appear to cause simplification or discontinuation of pulmonary vasodilator therapy. Longitudinal studies are needed to determine whether and how a LHD phenotype affects the use and effects of PAH drugs in the elderly.

Assessment of right ventricle in pulmonary arterial hypertension with three-dimensional echocardiography and cardiovascular magnetic resonance

AIM

To correlate 3-D Echo and CMR RV parameters and to verify whether they are similarly related to the clinical conditions of patients with pulmonary arterial hypertension (PAH), a disease in which the RV plays a crucial prognostic role.

METHODS

We enrolled 34 consecutive PAH patients followed by our PAH clinics. All patients underwent a 3-D Echo and CMR assessment of RV volumes and functions in the same day. The presence or absence of correlation between major findings was investigated; functional RV parameters were also analyzed in relation to 6-min walking test (6MWT) results and BNP/Nt-proBNP plasma levels. Twenty-four subjects served as controls.

RESULTS

Good agreement was found between 3-D Echo and CMR measures of RV volumes [RV-end-diastolic volume (r = 0.72, P < 0.0001), RV-end-systolic volume (ESV) (r = 0.80, P < 0.0001)] and function [RV-EF (r = 0.73, P < 0.0001), RV-ESV/SV (r = 0.83, P = 0.001)] for all the subjects of the study. These correlations were stronger in PAH patients than in control subjects. Importantly, 3-D Echo and CMR RV-EF and RV to pulmonary arterial coupling (RV-ESV/SV) similarly correlated with BNP/Nt-proBNP levels and with functional capacity measured at 6MWT in the PAH patients group.

CONCLUSIONS

3-D Echo demonstrated a significant agreement with CMR in the assessment of RV volume and function in PAH patients. Both techniques showed a similar correlation with clinical and prognostic parameters. The use of 3-D Echo should be amply boosted in the real-world clinical evaluation of PAH patients.

Hemodynamics and risk assessment 2 years after the initiation of upfront ambrisentan‒tadalafil in pulmonary arterial hypertension

BACKGROUND

Upfront combination therapy with ambrisentan and tadalafil has been reported to improve the condition of patients with pulmonary arterial hypertension (PAH) more than with either drug alone. However, little is known about the long-term associated changes in hemodynamics and risk assessment scores.

METHODS

This was a multicenter, retrospective analysis of clinical data in 106 patients with newly diagnosed PAH. Clinical evaluations, including demographics, medical history, World Health Organization (WHO) functional class (FC) and 6-minute walk distance (6MWD), right heart catheterization, and Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) risk score 2.0, were assessed over 48 months of ambrisentan‒tadalafil therapy.

RESULTS

At baseline, 9 patients (9%) showed a low (<7), 48 patients (45%) showed an intermediate (7-8), and 49 patients (46%) showed a high (>8) REVEAL risk score. At a median follow-up of 2 years, 45 patients (43%) showed a low, 47 patients (44%) showed an intermediate, and 14 patients (13%) showed a high REVEAL score, along with improvements in WHO FC, 6MWD and a decrease in mean pulmonary artery pressure and N-terminal pro brain natriuretic peptide (all p < 0.001). Pulmonary vascular resistance (PVR) decreased by 37% from 11.5 ± 6.5 to 7.2 ± 4.1 Wood units (p < 0.001). A total of 61 patients (57%) remained in intermediate-risk or high-risk categories. Low-risk patients had either a decrease in PVR of >50% or a stroke volume within the limits of normal.

CONCLUSIONS

Initial combination therapy with ambrisentan and tadalafil in PAH improves the REVEAL risk score in proportion to decreased PVR and preserved stroke volume but still insufficiently so in approximately 50% of the patients.

Hemodynamics and risk assessment 2 years after the initiation of upfront ambrisentan‒tadalafil in pulmonary arterial hypertension

BACKGROUND

Upfront combination therapy with ambrisentan and tadalafil has been reported to improve the condition of patients with pulmonary arterial hypertension (PAH) more than with either drug alone. However, little is known about the long-term associated changes in hemodynamics and risk assessment scores.

METHODS

This was a multicenter, retrospective analysis of clinical data in 106 patients with newly diagnosed PAH. Clinical evaluations, including demographics, medical history, World Health Organization (WHO) functional class (FC) and 6-minute walk distance (6MWD), right heart catheterization, and Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) risk score 2.0, were assessed over 48 months of ambrisentan‒tadalafil therapy.

RESULTS

At baseline, 9 patients (9%) showed a low (<7), 48 patients (45%) showed an intermediate (7-8), and 49 patients (46%) showed a high (>8) REVEAL risk score. At a median follow-up of 2 years, 45 patients (43%) showed a low, 47 patients (44%) showed an intermediate, and 14 patients (13%) showed a high REVEAL score, along with improvements in WHO FC, 6MWD and a decrease in mean pulmonary artery pressure and N-terminal pro brain natriuretic peptide (all p < 0.001). Pulmonary vascular resistance (PVR) decreased by 37% from 11.5 ± 6.5 to 7.2 ± 4.1 Wood units (p < 0.001). A total of 61 patients (57%) remained in intermediate-risk or high-risk categories. Low-risk patients had either a decrease in PVR of >50% or a stroke volume within the limits of normal.

CONCLUSIONS

Initial combination therapy with ambrisentan and tadalafil in PAH improves the REVEAL risk score in proportion to decreased PVR and preserved stroke volume but still insufficiently so in approximately 50% of the patients.

Performing versus deferring coronary angioplasty based on functional evaluation of vessel stenosis by pressure measurements: a clinical outcome study

AIM

The present study aimed to prospectively evaluate whether application of the concept of fractional flow reserve (FFR) guides the immediate decision to perform or to defer coronary angioplasty in unselected consecutive patients with one or more angiographically intermediate (50-70%) stenoses and non-conclusive or lacking non-invasive testing.

METHODS

We studied 112 patients (81 males and 31 females, aged 31-81 years) including 71 multivessel disease patients (63%) and 30 patients (27%) with unstable symptoms. FFR was measured with the use of a pressure-wire after adenosine-induced hyperaemia and compared with quantitative coronary angiography in 171 stenoses. Coronary angioplasty was performed in the presence of an FFR < 0.75 and deferred if FFR was > or = 0.75. Cardiac events including death, myocardial infarction, recurrent angina or symptoms requiring repeated hospitalization and target vessel revascularization (TVR) were recorded during a median period of 34 months (interquartile range 9-54 months).

RESULTS

Coronary angioplasty was deferred based on FFR results in 54 patients (group I). In the remaining 58 patients, angioplasty was performed in one or more stenoses that were significant by FFR and deferred in non-significant stenoses (group II). Overall, coronary angioplasty was performed in 71 vessels (41%) and deferred in 100 (59%). Cumulative cardiac events occurred in 12.9% of group I patients and in 24.1% of group II patients (chi-squared = 1.57, P = 0.20). TVR was required in 5% of the stenoses untreated based on FFR result in both groups and in 12.6% of stenoses that underwent coronary angioplasty (chi-squared = 3.25, P = 0.07; relative risk = 2.5, 95% confidence interval = 0.88-8.61).

CONCLUSIONS

In patients with angiographically intermediate stenoses, functional evaluation by FFR to select lesions that do not need to be treated invasively is safe. Unnecessary angioplasty and stenting may be saved in more than one half of individual coronary stenoses. The risk of major cardiac events and TVR of functionally non-significant stenoses is lower than the risk associated with coronary angioplasty. Our observations further support the use of pressure wire for physiological assessment of coronary artery stenosis in the catheterization room.

[Acute myocardial infarction after wasp sting]

Myocardial infarction after wasp sting is a rare event and this complication has been described in only a few previous occasions. We report the case of a 77-year-old patient admitted to our hospital because of an anaphylactic shock after he was stung by a wasp on the fifth finger of the left hand. Within about half an hour he sustained an acute myocardial infarction. Possible pathogenetic mechanisms include severe hypotension due to hypovolemic shock and coronary spasm with subsequent thrombosis of coronary vessels developed after the release of vasoactive, inflammatory and thrombogenic substances contained in the hymenoptera venom.

Closed versus open endotracheal suctioning in preterm infants: effects on cerebral oxygenation and blood volume

The aim of our study was to compare, using near-infrared spectroscopy (NIRS), the effects on cerebral intracellular oxygenation and cerebral blood volume (CBV) of closed endotracheal suctioning (CS), which permits continuous ventilation of the patient, with open endotracheal suctioning (OS), which requires disconnection from the ventilator. Eleven preterm infants were studied. Each patient underwent one CS, followed, after 60 min, by one OS, or vice versa, three times during the same day. Modifications in CBV and oxidized cytochrome oxidase (CytO2) were continuously detected by NIRS; arterial oxygen saturation (SaO2) heart rate (HR), transcutaneous carbon dioxide tension and mean arterial blood pressure were simultaneously recorded. Significant reductions in HR and SaO2 were observed following OS; the magnitude and duration of these negative effects of suctioning were significantly reduced with CS. In addition, the decrease in CBV was more pronounced than following CS. No changes in CytO2 concentration were seen.

Comparative evaluation of the effects of indomethacin and ibuprofen on cerebral perfusion and oxygenation in preterm infants with patent ductus arteriosus

OBJECTIVE

To compare the effects on cerebral perfusion and oxygenation of intravenous ibuprofen and indomethacin as treatment for patent ductus arteriosus in preterm infants.

STUDY DESIGN

Sixteen infants receiving mechanical ventilation (< 31 weeks gestation) with patent ductus arteriosus received either 0.2 mg/kg indomethacin (n = 8) or 10 mg/kg ibuprofen (n = 8) infused over 1 minute. Near-infrared spectroscopy was used to measure changes in cerebral blood volume and in oxidized cytochrome oxidase concentration. Cerebral blood flow velocity in the pericallosal artery was measured using Doppler ultrasonography.

RESULTS

Indomethacin caused a significant reduction of CBV (maximal changes in cerebral blood volume: -320 +/- 171 microL/100 gm) and, in four of eight patients, a fall in oxidized cytochrome oxidase concentration (maximal change in oxidized cytochrome oxidase concentration in the eight patients: -0.68 +/- 0.98 mumol/L, NS). Cerebral blood flow velocity fell significantly. Ibuprofen caused no significant reduction of cerebral blood volume, oxidized cytochrome oxidase concentration, or cerebral blood flow velocity, whereas a significant increase of cerebral blood volume (+207 +/- 200 microL/100 gm) was observed after 60 minutes. Ductus closure was seen in six of eight infants after the first dose of indomethacin and in five of eight infants after the first dose of ibuprofen. The therapeutic cycle involved administration of a second and third dose, provided no side effects occurred. Treatment was effective in all infants.

CONCLUSION

Compared with indomethacin, treatment with ibuprofen does not significantly reduce cerebral perfusion and oxygen availability; the observed increase in cerebral blood volume requires further investigation.

Bronchopleural fistula: successful selective bronchial occlusion with a Fogarty's catheter in a preterm infant

A preterm infant (26 weeks' gestation) mechanically ventilated for respiratory distress syndrome developed severe interstitial emphysema of the right lung with a bronchopleural fistula, pneumothorax and mediastinal shift. Selective occlusion of the right main bronchus with a Fogarty's catheter produced rapid improvement in the clinical condition and radiological features. Occlusion of the main bronchus in a newborn with a bronchopleural fistula and pulmonary interstitial emphysema is an easily performed manoeuvre that can be life-saving.

[Rotavirus infections in a neonatal pathology unit]

From February to June 1981, 38 newborn babies admitted to a special care unit were examined to determine the incidence of rotavirus infections. Fecal specimens were collected from all babies on the fifth day after birth and thereafter weekly. The stool samples were examined with an immunoenzymatic test. Serum was collected from the newborn babies and from their mothers three days after delivery. Thereafter more serum was collected from the babies at intervals. Serum was also collected from the hospital staff. Rotavirus was detected in one or more of the stool samples taken from 20 (53%) of the 38 newborn babies. Of these 20, 11 (55%) were already positive in the first specimen. Three babies still had rotavirus in their faeces after four weeks. No relation was noted between the admission to one or the other of the two wards in the unit and the presence of rotavirus in their stools. Complement fixing antibody (CFA) titers in the babies were not different from those in the mothers. A decline of antibody levels was observed in all the babies whether they were rotavirus positive or negative. Only three of the babies without CFA in the first serum sample had a significant increase of the titer while rotavirus was not found in their stools. The CFA titer geometric mean was significantly higher for babies who were found to have rotavirus from the first stool sample than for those whose subsequent samples were found to be positive. Moreover, the CFA titer geometric mean for the hospital staff was significantly higher than that of the mothers. Mild gastrointestinal symptoms were observed in 70% of the newborn babies having rotavirus in their stool and in 39% of those without rotavirus. However, this difference did not prove to be significant.