Congenital Heart Disease in Adults with Autosomal Dominant Polycystic Kidney Disease

Monoallelic Loss-of-Function IFT140 Pathogenic Variants Cause Autosomal Dominant Polycystic Kidney Disease: A Confirmatory Study With Suspicion of an Additional Cardiac Phenotype

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease. While biallelic variants affecting IFT140 are responsible for Mainzer-Saldino syndrome (characterized by severe ciliopathy causing skeletal abnormalities, kidney disease, and cysts), monoallelic loss-of-function (LoF) variants have been recently reported as an important cause of ADPKD beyond PKD1/2 genes. Herein, we report 6 non-family-related cases of monoallelic IFT140 LoF variants, identified from 1,340 exomes sequenced for nephrological indications in our local database. Every patient presented with polycystic kidney disease. Furthermore, the mother of a boy diagnosed with Mainzer-Saldino syndrome with a biallelic variant affecting IFT140 presented with several bilateral cysts, revealed after kidney imaging, and was found to carry a pathologic frameshift IFT140 variation. As well as this particular Mainzer-Saldino case, our 6 additional patients confirm that heterozygous IFT140 frameshift variants are responsible for the cystic phenotype and kidney failure. Interestingly, of the 6 patients, 2 also exhibited dilated cardiomyopathy, which was of unknown origin, as no genetic cause was found after exome sequencing analysis, suggesting a potential connection between IFT140 and heart disease.

Case report: A novel occurrence of persistent left cranial vena cava coexisting with polycystic kidney disease in a cat

A 7-year-old castrated male Munchkin cat was presented with anorexia. This cat had been diagnosed with chronic kidney disease due to polycystic kidney disease. Tachycardia with a systolic murmur (grade III/VI) was auscultated and for further diagnosis, echocardiography was performed. Based on echocardiography, persistent left cranial vena cava (PLCVC) was suspected due to enlargement of the coronary sinus and confirmed by saline contrast echocardiography. The dilated coronary sinus compressed the left atrium, and left ventricular hypertrophy with the systolic anterior motion of the mitral valve, aortic regurgitation, and mitral regurgitation were identified. After medical management using atenolol, left atrial function and other hemodynamics of the heart were improved, including the disappearance of regurgitation and normalization of left ventricular wall thickness. This case report describes the echocardiographic characteristics, diagnostic procedures, and disease progression in a cat with PLCVC after medical management using atenolol. Additionally, this is the first report of a cat with PLCVC, coexisting with polycystic kidney disease.

Implementation of Rapid Genome Sequencing for Critically Ill Infants With Complex Congenital Heart Disease

BACKGROUND

Rapid genome sequencing (rGS) has been shown to improve care of critically ill infants. Congenital heart disease (CHD) is a leading cause of infant mortality and is often caused by genetic disorders, yet the utility of rGS has not been prospectively studied in this population.

METHODS

We conducted a prospective evaluation of rGS to improve the care of infants with complex CHD in our cardiac neonatal intensive care unit.

RESULTS

In a cohort of 48 infants with complex CHD, rGS diagnosed 14 genetic disorders in 13 (27%) individuals and led to changes in clinical management in 8 (62%) cases with diagnostic results. These included 2 cases in whom genetic diagnoses helped avert intensive, futile interventions before cardiac neonatal intensive care unit discharge, and 3 cases in whom eye disease was diagnosed and treated in early childhood.

CONCLUSIONS

Our study provides the first prospective evaluation of rGS for infants with complex CHD to our knowledge. We found that rGS diagnosed genetic disorders in 27% of cases and led to changes in management in 62% of cases with diagnostic results. Our model of care depended on coordination between neonatologists, cardiologists, surgeons, geneticists, and genetic counselors. These findings highlight the important role of rGS in CHD and demonstrate the need for expanded study of how to implement this resource to a broader population of infants with CHD.

Management of Hypertension and Associated Cardiovascular Disease in Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease is the most commonly inherited disease of the kidneys affecting an estimated 12,000,000 people in the world. Autosomal dominant polycystic kidney disease is a systemic disease, with a wide range of associated features that includes hypertension, valvular heart diseases, cerebral aneurysms, aortic aneurysms, liver cysts, abdominal hernias, diverticulosis, gross hematuria, urinary tract infections, nephrolithiasis, pancreatic cysts, and seminal vesicle cysts. The cardiovascular anomalies are somewhat different than in the general population and also chronic kidney disease population, with higher morbidity and mortality rates. This review will focus on cardiovascular diseases associated with autosomal dominant polycystic kidney disease and their management.

Isolated Double Orifice Mitral Valve in a Patient With Autosomal Dominant Polycystic Kidney Disease

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DOMV can be diagnosed with TTE alone.

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DOMV can either be syndromic or isolated.

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Asymptomatic DOMV does not require treatment.

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The link between ADPKD and DOMV warrants more study.

Renal Denervation Helps Preserve the Ejection Fraction by Preserving Endocardial-Endothelial Function during Heart Failure

Renal denervation (RDN) protects against hypertension, hypertrophy, and heart failure (HF); however, it is not clear whether RDN preserves ejection fraction (EF) during heart failure (HFpEF). To test this hypothesis, we simulated a chronic congestive cardiopulmonary heart failure (CHF) phenotype by creating an aorta-vena cava fistula (AVF) in the C57BL/6J wild type (WT) mice. Briefly, there are four ways to create an experimental CHF: (1) myocardial infarction (MI), which is basically ligating the coronary artery by instrumenting and injuring the heart; (2) trans-aortic constriction (TAC) method, which mimics the systematic hypertension, but again constricts the aorta on top of the heart and, in fact, exposes the heart; (3) acquired CHF condition, promoted by dietary factors, diabetes, salt, diet, etc., but is multifactorial in nature; and finally, (4) the AVF, which remains the only one wherein AVF is created ~1 cm below the kidneys in which the aorta and vena cava share the common middle-wall. By creating the AVF fistula, the red blood contents enter the vena cava without an injury to the cardiac tissue. This model mimics or simulates the CHF phenotype, for example, during aging wherein with advancing age, the preload volume keeps increasing beyond the level that the aging heart can pump out due to the weakened cardiac myocytes. Furthermore, this procedure also involves the right ventricle to lung to left ventricle flow, thus creating an ideal condition for congestion. The heart in AVF transitions from preserved to reduced EF (i.e., HFpEF to HFrEF). In fact, there are more models of volume overload, such as the pacing-induced and mitral valve regurgitation, but these are also injurious models in nature. Our laboratory is one of the first laboratories to create and study the AVF phenotype in the animals. The RDN was created by treating the cleaned bilateral renal artery. After 6 weeks, blood, heart, and renal samples were analyzed for exosome, cardiac regeneration markers, and the renal cortex proteinases. Cardiac function was analyzed by echocardiogram (ECHO) procedure. The fibrosis was analyzed with a trichrome staining method. The results suggested that there was a robust increase in the exosomes' level in AVF blood, suggesting a compensatory systemic response during AVF-CHF. During AVF, there was no change in the cardiac eNOS, Wnt1, or β-catenin; however, during RDN, there were robust increases in the levels of eNOS, Wnt1, and β-catenin compared to the sham group. As expected in HFpEF, there was perivascular fibrosis, hypertrophy, and pEF. Interestingly, increased levels of eNOS suggested that despite fibrosis, the NO generation was higher and that it most likely contributed to pEF during HF. The RDN intervention revealed an increase in renal cortical caspase 8 and a decrease in caspase 9. Since caspase 8 is protective and caspase 9 is apoptotic, we suggest that RDN protects against the renal stress and apoptosis. It should be noted that others have demonstrated a role of vascular endothelium in preserving the ejection by cell therapy intervention. In the light of foregoing evidence, our findings also suggest that RDN is cardioprotective during HFpEF via preservation of the eNOS and accompanied endocardial-endothelial function.