Introduction: Fetal growth restriction (FGR) is associated with a higher risk of perinatal morbidity and mortality, as well as long-term health issues in newborns. Currently, there is no effective medicine for FGR. Phosphodiesterase-5 (PDE-5) inhibitors have been shown in pre-clinical studies to improve FGR. This study aimed to evaluate the latest evidence about the clinical outcomes and safety of PDE-5 inhibitors for the management of FGR. Methods: Eight databases (PubMed, Embase, Medline, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, Chinese Biomedical Database and WangFang Database) were searched for English and Chinese articles published from the database inception to December 2023. Randomized controlled trials (RCTs) reporting the use of PDE-5 inhibitors in FGR were included. The quality of the RCTs was assessed using the Cochrane Risk of Bias Tool. Odds ratio and mean difference (MD) (95% confidence intervals) were pooled for meta-analysis. Results: From 253 retrieved publications, 16 studies involving 1,492 pregnant women met the inclusion criteria. Only sildenafil (15 RCTs) and tadalafil (1 RCT) were studied for FGR. Compared with the control group (placebo, no treatment, or other medication therapies), sildenafil increased birth weight, pregnancy prolongation and umbilical artery pulsatility indices. However, it also increased the risk of pulmonary hypertension in newborns, as well as headache and flushing/rash in mothers. There were no significant differences in gestation age, perinatal mortality or major neonatal morbidity, stillbirth, neonate death, infants admitted to neonatal intensive care unit, intraventricular hemorrhage and necrotizing enterocolitis in infants, as well as pregnancy hypertension and gastrointestinal side effects in mothers between the treatment and the control groups. Discussion: Sildenafil was the most investigated PDE-5 inhibitors for FGR. Current evidence suggests that sildenafil can improve birth weight and duration of pregnancy but at the same time increase the risk of neonatal pulmonary hypertension. It remains uncertain whether the benefits of sildenafil in FGR outweigh the risks and further high-quality RCTs are warranted. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=325909.

This review focuses on Pulmonary Alveolar Microlithiasis (PAM), an autosomal recessive genetic disorder characterized by calcium crystal deposits (microliths) resulting from loss of function of the SLC34A2 gene. PAM is a rare disease with approximately 1100 reported cases globally. The historical context of its discovery and the genetic, epidemiological, and pathophysiological aspects are discussed. PAM falls under interstitial lung diseases and is associated with pulmonary hypertension (PH), primarily categorized as Group 3 PH. The clinical manifestations, diagnostic approaches, and challenging aspects of treatment are explored. A clinical case of PAM with severe pulmonary hypertension is presented, emphasizing the importance of comprehensive evaluation and the potential benefits of phosphodiesterase-5 inhibitors (PDE5i) therapy. Despite limited therapeutic options and challenging diagnosis, this review sheds light on recent developments and emerging treatments for PAM and associated pulmonary hypertension.

The treatment with phosphodiesterase-5 (PDE-5) inhibitors was postulated in heart failure (HF). We conducted a systematic review and a meta-analysis on their beneficial and adverse effects in patients with HF.
A meta-analysis of randomized trials evaluating the chronic use of PDE-5 inhibitors in patients with HF was conducted. Endpoints included death, HF hospitalizations, functional capacity, pulmonary pressures, quality of life, and adverse effects. Random-effects models were used to pool outcomes. Categorical data were summarized with relative risks (RR) and 95% confidence intervals (95%CI), and continuous data with weighted mean differences and standardized mean differences.
Sixteen studies (1119 participants) were included. No effect was observed on mortality (RR: 1.16; 95%CI: 0.50-2.66; I2: 0.0%) or HF hospitalizations (RR: 0.75; 95%CI: 0.41-1.37; I2: 38.7%). Treatment significantly reduced pulmonary systolic pressure (-10.64 mmHg; 95%CI: -5.14 to -16.15 mmHg; I2: 96.0%), and increased peak oxygen consumption (2.06 ml/kg/min; 95%CI: 0.40-3.72; I2: 89.6%), although with high inconsistency. There were no significant effects on quality of life (-0.15; 95%CI: -0.48-0.18; I2: 0.0%). On the other hand, the risk of headaches was increased (RR: 1.63; 95%CI: 1.11-2.39; I2: 0.0%). Publication bias was identified for HF hospitalizations.
Current data suggest that PDE-5 inhibitors therapy does not improve prognosis or quality of life among HF patients. Hemodynamic and functional effects could be relevant, and more studies are necessary to define its role.
El tratamiento con inhibidores de la fosfodiesterasa 5 (iFDE-5) fue postulado en la insuficiencia cardiaca (IC). Se realizó una revisión sistemática y metaanálisis sobre sus efectos beneficiosos y adversos en pacientes con IC.
Metaanálisis de ensayos clínicos aleatorizados que evaluaron el uso crónico de iFDE-5 en pacientes con IC. Los criterios de valoración finales incluyeron la muerte, las hospitalizaciones por IC, la capacidad funcional, las presiones y las resistencias pulmonares, la calidad de vida y los efectos adversos. Se utilizaron modelos de efectos aleatorios para agrupar los resultados. Los datos categóricos fueron resumidos como riesgos relativos (RR) e intervalos de confianza del 95% (IC95%), y los datos continuos como diferencias de medias ponderadas y diferencias de medias estandarizadas.
Se incluyeron 16 estudios (1119 participantes). No se observaron efectos sobre la mortalidad (RR: 1,16; IC95%: 0.50-2.66; I2: 0.0%) ni sobre las hospitalizaciones por IC (RR: 0,75; IC95%: 0.41-1.37; I2: 38.7%). El tratamiento redujo significativamente la presión sistólica pulmonar (−10,64 mmHg; IC95%: −5.14 a −16.15 mmHg; I2: 96.0%) e incrementó el consumo máximo de oxígeno (2.06 ml/kg/min; IC95%: 0.40-3.72 ml/kg/min; I2: 89.6%), aunque con elevada inconsistencia. No se detectaron efectos significativos sobre la calidad de vida (−0.15; IC95%: −0.48-0.18; I2: 0.0%). Por otra parte, aumentó el riesgo de cefaleas (RR: 1.63; IC95%: 1.11-2.39; I2: 0.0%). Se identificó un sesgo de publicación para las hospitalizaciones por IC.
Los datos actuales sugieren que el tratamiento con iFDE-5 no mejora el pronóstico ni la calidad de vida de los pacientes con IC. Los efectos hemodinámicos y funcionales podrían ser relevantes, y son necesarios más estudios para definir su rol.

Poudel, Sangeeta, Sandesh Gautam, Purushottam Adhikari, and Ken Zafren. Physiological effects of sildenafil versus placebo at high altitude: a systematic review. High Alt Med Biol. 25:16-25, 2024. Introduction: High altitude pulmonary edema (HAPE), a life-threatening condition that affects individuals ascending to high altitude, requires the development of pulmonary hypertension. Sildenafil can be used to prevent and treat HAPE, presumably by decreasing pulmonary artery pressure (PaP). We compared the physiological effects of sildenafil versus placebo at high altitude (above 2,500 m), including the effects on PaP. Methods: We performed a systematic search of PubMed, EMBASE, and Cochrane CENTRAL for randomized controlled studies of the physiological effects of sildenafil in hypoxia in healthy individuals. We conducted a systematic review of all studies meeting our criteria. Results: Of the 14 studies that met the inclusion criteria, 8 were hypobaric hypoxia studies. Six studies reported data at rest at altitudes from 3,650 to 5,245 m. Two were simulations reporting exercise data at equivalent altitudes of 2,750-5,000 m. Nine studies used normobaric hypoxia corresponding to altitudes between 2,500 and 6,400 m. One reported only rest data, two reported rest and exercise data, and the others reported only exercise data. Sildenafil significantly reduced PaP at rest and exercise in hypobaric or normobaric hypoxia. There were no significant differences between arterial oxygen saturation (SpO2) with sildenafil in hypobaric or normobaric hypoxia at rest or exercise. There were no significant differences in heart rate or mean arterial pressure (MAP) at rest or exercise and cardiac output during exercise in hypobaric or normobaric hypoxia. Conclusions: Sildenafil significantly reduces PaP at rest and exercise in normobaric or hypobaric hypoxia. Sildenafil has no significant effects on SpO2, heart rate, cardiac output (during exercise), or MAP at rest or exercise in hypobaric or normobaric hypoxia.

UNASSIGNED: Three selective and most used inhibitors of PDE-5-sildenafil, vardenafil and tadalafil- have been successfully used for the treatment of erectile dysfunction. Erectile dysfunction and cardiovascular diseases might be considered as two dissimilar clinical signs of the identical systemic disease. PDE-5 inhibitors can through different models and mechanisms induce vasodilation, decrease apoptosis and cell proliferation, and they are widely present in various tissues that make them promising targets in a range of cardiovascular diseases.
UNASSIGNED: PubMed was explored to identify papers published from 1990-2019, presenting data for the most used PDE-5 inhibitors (sildenafil, tadalafil or vardenafil) in treatment of cardiovascular diseases.
UNASSIGNED: This article analyses the therapeutic potentials of PDE-5 inhibitors in cardiovascular diseases and discusses mechanisms, possible risks and limitations. Comparable to earlier studies, newer studies suggest cardioprotective effects of PDE-5 inhibitors, which include different models and mechanisms and do not indicate an increased rate of significant cardiovascular adverse reactions. Dissimilarity in the pharmacokinetics and pharmacodynamics of PDE-5 inhibitors are significant to their risk- benefit profile and clinical use. Some of the studies suggesting infarct size reduction after PDE-5 inhibition described the especially close dose-effect relation, other studies dosage adaptation in drug- drug interactions.
UNASSIGNED: PDE-5 inhibitors indicate the encouraging useful effects by ischemia/reperfusion injury, myocar-dial infarction, cardiac hypertrophy, cardiomyopathy and systolic and diastolic congestive heart failure. Therefore, this and similar reviews can help for additional clinical targeting in the therapy of cardiovascular diseases.

Sildenafil is a medication used for the treatment of erectile dysfunction. It was approved by the U.S. Food and Drug Administration (FDA) in 1998. Several articles have raised concerns regarding the use of sildenafil and the occurrence of serious adverse events, such as myocardial ischemia, stroke, and even death. Our aim is to systematically review the existing literature on mortality associated with sildenafil use. The method used for this systematic review was completed by searching three databases: PubMed, Scopus, and Web of Science. Articles were screened and assessed for eligibility. This review uses the articles found to address the concerns associated with sildenafil and mortality. A total of 19 reports were used in our systematic review, in which there were 10 case reports, two case series, three systematic reviews, one narrative review, one retrospective study, one article in the British Medical Journal, and one commentary article. One FDA article in particular included case reports and reports to the FDA on the use of sildenafil eight months after its introduction to the market in 1998, with 522 deaths reported. Another retrospective study examined the use of sildenafil on infants below the age of 1 who did not have congenital heart disease but did suffer from severe pulmonary hypertension. The study found a mortality rate of 29%, which increased with sildenafil dosage. A case series examined six deaths related to non-prescription use of sildenafil. All these cases were subjected to autopsies and related to sexual activity. The study suggests that phosphodiesterase 5 inhibitors induced the deaths, and the concentration of sildenafil in the femoral blood was found to be between 0.032and0.087 μg. To conclude, the literature available on this topic is deemed insufficient to provide enough data to establish a direct link of causality between sildenafil and mortality. Although some studies paint sildenafil as the culprit behind these deaths, further studies and research are needed to explain the unexpected deaths following sildenafil use.

Background: Despite the improvement in left ventricular assist device (LVAD) technology and the advent of third-generation LVADs, hemocompatibility-related events remain a significant issue. Therefore, new pharmacological treatments are necessary to optimize patient management and to further reduce hemocompatibility-related events. The purpose of the present systematic review and meta-analysis was to summarize the existing data regarding the safety and efficacy of post-implant phosphodiesterase-5 inhibitors (PDE-5i) on hemocompatibility-related events. Methods: Among the 258 articles in Pubmed, Scopus, and CENTRAL that were retrieved (1990−2022), 15 studies were included in the qualitative synthesis, and 9 studies were included in the quantitative synthesis. The fixed-effects model was used because it is statistically sound for combining a very small number of studies. The primary endpoint of the study was all-cause mortality, whereas the secondary endpoints were ischemic stroke, pump thrombosis, and gastrointestinal bleeding. Results: Mortality was significantly lower in the PDE-5i group vs. the control group (OR: 0.92 [95% CI: 0.85, 0.98]; p = 0.02). The secondary endpoints ischemic stroke (OR: 0.87 [95% CI: 0.78, 0.98]; p = 0.02) and pump thrombosis (OR: 0.90 [95% CI: 0.82, 0.99]; p = 0.04) were also lower in the PDE-5i group. The incidence of gastrointestinal bleeding was significantly higher in patients with LVAD receiving PDE-5i (OR: 1.26 [95% CI: 1.11, 1.44]; p < 0.01). In the overall analysis, the heterogeneity of outcomes was low, except for pump thrombosis. Conclusions: The use of PDE-5i post-implant was associated with lower mortality and thrombotic events but with a higher risk of gastrointestinal bleeding.

BACKGROUND: Phosphodiesterase-5 inhibitors (PDE5-Is), used in the management of erectile dysfunction (ED), have potential cardioprotective benefits. The impact of PDE5-Is on reducing adverse cardiovascular outcomes in patients with diabetes mellitus (DM) and ED is uncertain. Using a systematic review and meta-analysis of observational cohort studies and randomised controlled trials (RCTs), we evaluated if (i) the association of PDE5-Is in people with ED and DM and their risk of cardiovascular disease (CVD) and mortality and (ii) ED confers an excess risk of CVD and mortality in patients with DM compared with no DM.
METHODS: Studies were identified from MEDLINE, Embase, the Cochrane Library, Web of Science citation search and search of bibliographies to April 2022. Study-specific risk ratios (RRs) with 95% confidence intervals (CIs) were pooled.
RESULTS: Eighteen unique studies reported on the cardiovascular impact of ED in patients with and without DM. In the general population, the RRs (95% CIs) of ED for composite CVD/MACE, all-cause mortality, CHD and stroke were 1.43 (1.31-1.55), 1.47 (1.31-1.65), 1.59 (1.39-1.82), and 1.34 (1.15-1.56), respectively. The respective estimates were 1.68 (1.15-2.45), 1.40 (0.90-2.18), 1.41 (1.24-1.61) and 1.32 (1.09-1.60) in the diabetes population. Interaction analyses suggested similar risk in both populations. Six studies reported the cardiovascular effects of PDE5-Is in people with ED and DM. Limited RCT data showed no significant differences in the risk of major adverse cardiac event (MACE), coronary heart disease (CHD) and all-cause mortality comparing PDE5-I use with non-use: RRs (95% CIs) of 3.47 (0.17-69.19), 1.31 (0.10-16.54) and 0.35 (0.12-1.05), respectively.
CONCLUSIONS: ED confers no excess risk of CVD and mortality in patients with DM compared with no DM. Limited and inadequately powered data shows no significant differences in the risk of adverse cardiovascular outcomes comparing use of PDE5-Is with non-use in patients with ED and DM. PROSPERO Registration: CRD42022324537.

The efficacy and safety profile of phosphodiesterase-5 inhibitors (PDE-5i) in pregnancy are unclear from the few relatively small diverse studies that have used them.
To assess the safety profile and clinical outcomes of PDE-5i use in pregnancy.
We searched Embase, PubMed, CENTRAL, Prospero and Google Scholar to identify randomised controlled trials (RCTs) reporting the use of any PDE-5i in pregnancy up to September 2021.
RCTs reporting obstetric or perinatal outcomes or maternal adverse outcomes in women taking PDE5i in pregnancy.
Risk ratios (RR), 95% confidence intervals (95% CI) and 95% prediction intervals were calculated and pooled for analysis.
We identified 1324 citations, of which 10 studies including 1090 participants met the inclusion criteria. Only tadalafil and sildenafil were reported as used in pregnancy. Two studies using tadalafil and eight sildenafil. Nine of ten studies were assessed at having of low risk of bias. PDE-5i use was associated with an increased risk of headaches (RR 1.41, 95% CI 0.97-2.05), flushing (RR 2.59, 95% CI 0.69-9.90) and nasal bleeding (RR 10.53, 95% CI 1.36-81.3); an increase in vaginal birth when used for non-fetal growth restriction (FGR) indications (RR 1.24, 95% CI 1.00-1.55) and a reduction in risk of operative birth for intrapartum fetal compromise (RR 0.58, 95% CI 0.38-0.88). There was no evidence of any increase in risk of perinatal death (RR 0.89, 95% CI 0.56-1.43). However, use for the treatment of FGR increased the risk of persistent pulmonary hypertension of the newborn (PPHN) (RR 2.52, 95% CI 1.00-6.32).
This meta-analysis suggests PDE-5i use in pregnancy is associated with mild maternal side effects and lower risk of operative birth for intrapartum fetal distress. Prolonged use for the treatment of FGR may increase the risk of PPHN.
PDE-5i use in pregnancy is associated with mild maternal side effects, lower operative birth for intrapartum fetal distress and a possible increase in persistent pulmonary hypertension of the newborn when used for the treatment of fetal growth restriction.

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