Familiar clustering of aortic dissection in polycystic kidney disease

Cardiac Involvement in Autosomal Dominant Polycystic Kidney Disease

Cardiovascular disorders are the main complication in autosomal dominant polycystic kidney disease (ADPKD). contributing to both morbidity and mortality. This review considers clinical studies unveiling cardiovascular features in patients with ADPKD. Additionally, it focuses on basic science studies addressing the dysfunction of the polycystin proteins located in the cardiovascular system as a contributing factor to cardiovascular abnormalities. In particular, the effects of polycystin proteins’ deficiency on the cardiomyocyte function have been considered.

Risk of Ascending Aortic Aneurysm in Patients With Autosomal Dominant Polycystic Kidney Disease

In recent years, simple renal cysts have been associated with an increased risk of aortic aneurysms. There is little data regarding aortic dilation in patients with autosomal dominant polycystic kidney disease (ADPKD). The aim of this study was to compare Sinuses of Valsalva (SoV) and tubular ascending aorta diameters in ADPKD patients with matched controls. From 2008 to 2016, 61 consecutive ADPKD patients who had an echocardiogram performed in our institution were matched 1:1 with controls for sex, age, blood pressure, and β-blocker therapy use. SoV and tubular ascending aorta were measured at end-diastole, using the leading-edge to leading-edge convention. Paired t Tests were used for quantitative variables and McNemar-tests for qualitative variables. The mean age of patients was 56 ± 12 years, 54% were men, 38% received β-blockers, and mean systolic and diastolic BP were 137 ± 25 and 78 ± 19 mm Hg. SoV diameters were significantly larger in ADPKD patients than in controls (36.4 ± 4.1 vs 34.0 ± 3.7 mm, p <0.0001). The Z-scores (normalized for sex, age, and body surface area) were significantly higher in ADPKD patients, both for SoV and tubular ascending aorta. Moreover, aortic aneurysms, as defined by a Z score >2 standard deviations, were present in 27 ADPKD patients (44%) versus 9 controls (15%, p <0.001). In conclusion, there is an increased prevalence of aortic aneurysms in ADPKD patients as compared with controls matched for common confounding factors for aortic dilation.

Autosomal dominant polycystic kidney disease and coronary artery dissection or aneurysm: a systematic review

IMPORTANCE

Autosomal dominant polycystic kidney disease (ADPKD) has been associated with cardiovascular abnormalities such as intracranial and aortic aneurysms.

OBJECTIVE

To systematically review the case reports and case series of ADPKD patients with coronary artery dissection or aneurysm. Evidence review Systematic review registration number: CRD42015015723.

DATA SOURCES

MEDLINE, Web of Science and OpenGrey, reference lists of studies.

STUDY SELECTION

Published case reports and case series.

DATA EXTRACTION

Two parties analyzed the studies. Disagreements were solved by consensus or by a third party.

FUNDING

none. Findings The reports of 23 patients (22 from 17 studies--six with coronary artery dissection and 16 with coronary artery aneurysm--and one with coronary dissection) were analyzed and reported here. Most patients were symptomatic. Coronary dissection showed female and left descending anterior artery predominance, features similar to non-ADPKD patients, but a median diagnostic age below expected (41 vs. 50 years old). Coronary aneurysms had male and right coronary artery predominance but lower median diagnostic age (44 years old) and higher rate of multiple vessel affection than reported for non-ADPKD patients.

CONCLUSION AND RELEVANCE

Clinical disparities may suggest a different mechanism of aneurysm formation compared to the population without ADPKD. Nevertheless, lack of access to data of one patient and text of one article limited our conclusions. Coronary aneurysms and dissections represent a source of coronary syndromes and death in ADPKD. Mutation of ADPKD-related genes may predispose to coronary abnormalities, especially aneurysms. Further analysis regarding this association is necessary.

Dissecting aneurysm in a patient with autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is primarily associated with renal failure, but it also causes systemic diseases, including cysts of other systemic organs and cerebral or visceral aneurysm. To make matters worse, life-threatening aortic diseases are associated with ADPKD in some cases. However, only a few reports of ADPKD-associated with thoracic aortic dissection have been published. Herein, we present a case of dissecting aneurysm in a patient with hypertension and ADPKD. He had been followed up for type B aortic dissection for six years. Preoperative creatinine level ranged from 2.1 to 2.4 mg/dl. We performed replacement of the thoracic aorta with prosthetic graft successfully, and postoperatively, dialysis was not required.It is very important for us to recognize the relationship between ADPKD and thoracic aortic dissection, which can cause high mortality and morbidity rates.

The role of the renin-angiotensin system in thoracic aortic aneurysms: clinical implications

Thoracic aortic aneurysms (TAAs) are a potential life-threatening disease with limited pharmacological treatment options. Current treatment options are aimed at lowering aortic hemodynamic stress, predominantly with β-adrenoceptor blockers. Increasing evidence supports a role for the renin-angiotensin system (RAS) in aneurysm development. RAS blockade would not only lower blood pressure, but might also target the molecular pathways involved in aneurysm formation, in particular the transforming growth factor-β and extracellular signal-regulated kinase 1/2 pathways. Indeed, the angiotensin II type 1 (AT₁) receptor blocker losartan was effective in lowering aortic root growth in mice and patients with Marfan's syndrome. RAS inhibition (currently possible at 3 levels, i.e. renin, ACE and the AT₁ receptor) is always accompanied by a rise in renin due to interference with the negative feedback loop between renin and angiotensin II. Only during AT₁ receptor blockade will this result in stimulation of the non-blocked angiotensin II type 2 (AT₂) receptor. This review summarizes the clinical aspects of TAAs, provides an overview of the current mouse models for TAAs, and focuses on the RAS as a new target for TAA treatment, discussing in particular the possibility that AT₂ receptor stimulation might be crucial in this regard. If true, this would imply that AT₁ receptor blockers (and not ACE inhibitors or renin inhibitors) should be the preferred treatment option for TAAs.

Polycystins, focal adhesions and extracellular matrix interactions

Polycystic kidney disease is the most common heritable disease in humans. In addition to epithelial cysts in the kidney, liver and pancreas, patients with autosomal dominant polycystic kidney disease (ADPKD) also suffer from abdominal hernia, intracranial aneurysm, gastrointestinal cysts, and cardiac valvular defects, conditions often associated with altered extracellular matrix production or integrity. Despite more than a decade of work on the principal ADPKD genes, PKD1 and PKD2, questions remain about the basis of cystic disease and the role of extracellular matrix in ADPKD pathology. This review explores the links between polycystins, focal adhesions, and extracellular matrix gene expression. These relationships suggest roles for polycystins in cell-matrix mechanosensory signaling that control matrix production and morphogenesis. This article is part of a Special Issue entitled: Polycystic Kidney Disease.

Spontaneous coronary artery dissection in a woman with polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD), characterized by renal cyst formation, is known to cause such vascular abnormalities as arterial dilatation and dissection. However, spontaneous coronary artery dissection (SCAD) is observed only rarely in patients with ADPKD. We report a patient with ADPKD who developed SCAD and presented with acute myocardial infarction. Her coronary angiography showed a long spiral dissection of the left anterior descending coronary artery. She underwent successful coronary angioplasty with insertion of 3 drug-eluting stents. To the best of our knowledge, this is the first reported case of percutaneous coronary intervention for coronary dissection in a patient with ADPKD. The pathophysiological characteristics of vascular complications in patients with ADPKD are discussed. Polycystins are strongly expressed in human adult vascular smooth muscle cells, and the vascular abnormalities in patients with ADPKD may be related to altered expression of polycystins. Because early recoginition and prompt efforts at mechanical reperfusion, if indicated, are crucial for successful management of SCAD, it would be worthwhile to consider SCAD in the differential diagnoses of acute coronary syndrome in patients with ADPKD.

Gene expression in acute Stanford type A dissection: a comparative microarray study

Background

We compared gene expression profiles in acutely dissected aorta with those in normal control aorta.

Materials and methods

Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas™ Human1.2 Array I, BD Atlas™ Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip^®. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function.

Results

According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV α2 and -α5, collagen VI α3, collagen XIV α1, collagen XVIII α1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., α-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection.

Conclusion

Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

The coexistence of acute aortic dissection with autosomal dominant polycystic kidney disease--description of two hypertensive patients

BACKGROUND

Acute aortic dissection is a rare but potentially lethal disease characterized by high early mortality when left untreated. However, survival may be significantly improved by the timely institution of appropriate medical and/or surgical therapy. Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common hereditary disorders, accounting for 8-10% of the cases of end-stage renal disease. Hypertension occurs frequently and is an early manifestation of ADPKD in approximately 50-70% of non-azotemic patients. ADPKD, often caused by mutations in the PKD1 gene, is associated with life-threatening vascular abnormalities that are commonly attributed to the frequent occurrence of hypertension.

METHODS

We present two cases of hypertensive patients with acute aortic dissection (type A Stanford) coexisting with ADPKD.

RESULTS

A 54-year-old male hypertensive patient and a 47-year-old male hypertensive patient, both with known ADPKD were diagnosed and operated with acute dissection of ascending aorta. Both patients were characterized by severe hypertension; therefore, in both cases, degree of hypertension is likely to be causative for this vascular complication. However, since ADPKD is associated with the vascular complications mentioned above, abnormality of the structure of the arterial wall of the thoracic aorta cannot be ruled out.

CONCLUSION

Aortic dissection is a rare but potentially disastrous complication, and clinicians should always consider this when dealing with patients with ADPKD who present with chest pain or collapse.

Gene expression profiles in the acutely dissected human aorta

OBJECTIVES

heritable connective tissue abnormalities and arterial hypertension may predispose to aortic dissection. This study evaluates gene expression profiles in the acutely dissected human aorta.

DESIGN, MATERIALS AND METHODS

Atlas Human Broad Arrays I, II, and III (Clontech) were used to compare gene expression in acutely dissected (6 patients) and normal ascending aortas (6 multiorgan donors). The tissues were also compared macroscopically.

RESULTS

of 3537 genes analysed, 1250 (35%) were expressed in aortic tissue. For statistical analysis we focused on 627 genes, which had an intensity>0.95 of the mean patients or controls. Dissected and adjacent macroscopically intact aorta displayed similar gene expression patterns. On the contrary, 66 genes were expressed significantly different in dissected aorta, compared with undiseased control aorta of multiorgan donors. Genes, predominantly upregulated in dissection, are involved in inflammation, in extracellular matrix proteolysis, in proliferation, translation and transcription. Predominantly downregulated genes code for extracellular matrix proteins, adhesion proteins and cytoskeleton proteins.

CONCLUSION

our results demonstrate for the first time the complexity of the dissecting process on a molecular level. The ultimate dissection seems to be the dramatic endpoint of a long-lasting process of degradation and insufficient remodelling of the aortic wall. Altered patterns of gene expression suggest a pre-existing structural failure of the aortic wall, resulting in dissection.

Endothelium-dependent relaxation of small resistance vessels is impaired in patients with autosomal dominant polycystic kidney disease

Impaired endothelium-dependent relaxation has been demonstrated previously in resistance vessels of Han:SPRD polycystic kidney disease rats. The aim of the present study was to investigate whether endothelium-dependent relaxation is reduced also in patients with autosomal dominant polycystic kidney disease (ADPKD) and whether this is influenced by the nitric oxide (NO) system. Small subcutaneous resistance vessels from normotensive ADPKD patients with normal or near-normal renal function (n = 9) and from healthy control subjects (n = 10) were mounted in a Mulvany-Halpern myograph. The morphology of the vessels and acetylcholine (ACh)-induced endothelium-dependent relaxation, as well as 3-morpholino-sydnonimine (SIN-1, NO donor)-induced endothelium-independent relaxation were investigated. The results showed that: (1) there were no significant differences in morphologic parameters of resistance vessels between the two groups; (2) the maximal ACh-induced relaxation rate was decreased in ADPKD patients compared with control subjects (71.5 +/- 12.1 versus 85.2 +/- 8.7%, P < 0.01); (3) in the presence of L-arginine (a substrate of NO synthase), a left shift of the ACh dose-response curves was found in control subjects, but not in ADPKD patients; (4) in the presence of the N(G)-nitro-L-arginine methyl ester (an inhibitor of NO synthase), a right shift of the ACh dose-response curve was found in control subjects, but not in ADPKD patients; and (5) endothelium-independent relaxation rate induced with SIN-1 was similar in patients and control subjects. In conclusion, endothelium-dependent relaxation was impaired in resistance vessels from patients with ADPKD. The reduced response of the vessels to both the substrate and inhibitor of NO synthase in ADPKD suggests that an impairment of NO synthase may be involved in the mechanism of endothelial dysfunction in ADPKD.

Familial phenotype differences in PKD11

Familial phenotype differences in PKD1.

BACKGROUND

Mutations within the PKD1 gene are responsible for the most common and most severe form of autosomal dominant polycystic kidney disease (ADPKD). Although it is known that there is a wide range of disease severity within PKD1 families, it is uncertain whether differences in clinical severity also occur among PKD1 families.

METHODS

Ten large South Wales ADPKD families with at least 12 affected members were included in the study. From affected members, clinical information was obtained, including survival data and the presence of ADPKD-associated complications. Family members who were at risk of having inherited ADPKD but were proven to be non-affected were included as controls. Linkage and haplotype analysis were performed with highly polymorphic microsatellite markers closely linked to the PKD1 gene. Survival data were analyzed by the Kaplan-Meier method and the log rank test. Logistic regression analysis was used to test for differences in complication rates between families.

RESULTS

Haplotype analysis revealed that each family had PKD1-linked disease with a unique disease-associated haplotype. Interfamily differences were observed in overall survival (P = 0.0004), renal survival (P = 0.0001), hypertension prevalence (P = 0.013), and hernia (P = 0.048). Individuals with hypertension had significantly worse overall (P = 0.0085) and renal (P = 0.03) survival compared with those without hypertension. No statistically significant differences in the prevalence of hypertension and hernia were observed among controls.

CONCLUSION

We conclude that phenotype differences exist between PKD1 families, which, on the basis of having unique disease-associated haplotypes, are likely to be associated with a heterogeneous range of underlying PKD1 mutations.

Aortic pain

With the exception of the pain of acute aortic dissection, the thoracic aorta is not usually considered as a pain-producing organ. However, nineteenth century clinicians considered the aorta as a source of cardiovascular pain in the presence of autopsy-documented inflammatory aortitis, aortic aneurysms, and arterial hypertension, whereas early in the twentieth century, aortic pain reactions were elicited in experimental studies involving distension of the ascending aorta or the application of stimulating substances to the outer surface of the aorta. More recently, increased attention to aortic elastic properties, and to aortic vascular biology at the molecular level refocused interest on the many facets of aortic function beyond that of a simple conduit. The recognition of pain of thoracic aortic origin now extends to patients with progressive aortic syndromes such as aortic intramural hematoma, aortic intimal tears, aortic penetrating ulcers, aortic root dilatation without dissection in connective tissue disorders, inflammatory aortopathies, and abnormalities of aortic distensibility. The occurrence of pain during balloon inflation at balloon angioplasty of aortic coarctation, which disappears immediately after deflation, is the modern equivalent of the early experimental studies. The authors present a consideration of thoracic aortic pain in light of contemporary concepts in cardiovascular medicine with roots in the rich historical reservoir of information about aortic function and disease.

The pathogenesis of hypertension in autosomal dominant polycystic kidney disease

BACKGROUND

Hypertension is a common and serious complication of autosomal dominant polycystic kidney disease (ADPKD), often occurring early in the disease before the renal function starts to decrease. The pathogenesis of this early hypertension is controversial.

OBJECTIVE

To review studies on the pathogenesis of early and late hypertension in ADPKD.

STUDY SELECTION

Studies on ADPKD and hypertension were retrieved from Medline from the last 20 years, with an emphasis on the last 10 years. These studies, together with selected published abstracts from recent hypertension and nephrology meetings, were reviewed critically.

RESULTS

Cyst growth, renal handling of sodium, activation of the renin-angiotensin-aldosterone system, volume expansion, an elevated plasma volume, and increased plasma atrial natriuretic peptide and plasma endothelin levels have all been found to be associated with hypertension in ADPKD. In some studies an inappropriate activity of the renin-angiotensin-aldosterone system that could be related to cyst growth and intrarenal ischemia was found. An increase in renal vascular resistance has been demonstrated and might be caused by intrarenal release of angiotensin II. Interestingly, the protective effect of angiotensin converting enzyme inhibitors on the renal function could not be demonstrated in ADPKD patients with a moderately decreased renal function. The importance, if any, of endothelial vasodilatory factors is not known. Sympathetic nervous activity seems to be increased in ADPKD, but the importance of this for the blood pressure level is not known.

CONCLUSION

The pathogenesis of hypertension in ADPKD is complex and likely to be dependent on the interaction of hemodynamic, endocrine and neurogenic factors.

Thoracic Aortic Aneurysms: Role of Echocardiography

This article describes the evolving role of echocardiography for the detection and evaluation of thoracic aortic aneurysms. A brief summary of the clinical, anatomical, and pathological features of the etiologic categories of thoracic aneurysms is presented. The advantages and limitations of echocardiography and its comparison with other techniques (computed tomographic scanning, magnetic resonance imaging, and aortography) are discussed. (ECHOCARDIOGRAPHY, Volume 13, March 1996)

Polycystic kidney disease: etiology, pathogenesis, and treatment

Once viewed as hopelessly incurable disorders and the dustbin for careers in academic medicine, the polycystic kidney diseases have emerged as prime targets of pathophysiologic study and palliative and definitive treatment in the era of molecular medicine. Polycystic kidney disease (PKD) may be hereditary or acquired. The major inherited types are autosomal dominant (AD) and autosomal recessive (AR). ADPKD is caused by at least two (and possibly three) genes located on separate chromosomes, while ADPKD-1 is due to a 14 kb transcript in a duplicated region on the short arm of chromosome 16 very near the alpha-globin gene cluster and the gene for one form of tuberous sclerosis. ADPKD-2 has been assigned to the long arm of chromosome 4. ARPKD is due to a mutated gene on both copies of the long arm of chromosome 6. Cysts originate in renal tubules. Proliferation of tubule epithelial cells modulated by endocrine, paracrine, and autocrine factors is a major element in the pathogenesis of renal cystic diseases. In addition, fluid that is abnormally accumulated within the cysts is derived from glomerular filtrate and, to a greater extent, by transepithelial fluid secretion. Abnormal synthesis and degradation of matrix components associated with interstitial inflammation are additional features in the pathogenesis of renal cystic diseases. The ADPKD genotypes are characterized by bilateral kidney cysts, hypertension, hematuria, renal infection, stones, and renal insufficiency. ADPKD is a systemic disorder; cysts appear with decreasing frequency in the kidneys, liver, pancreas, brain, spleen, ovaries, and testis. Cardiac valvular disorders, abdominal and inguinal hernias, and aneurysms of cerebral and coronary arteries and aorta are also associated with ADPKD. Treatment is supportive: dietary regulation of salt and protein intake, control of hypertension and renal stones, and dialysis and transplantation at the end stage. ARPKD is a relatively rare disease that causes clinical symptoms at birth, with significant mortality in the first month of life. The cysts develop primarily in the collecting ducts because of a failure in the maturation process. Early complications include Potter's syndrome; excessive size of the kidneys, causing respiratory dysfunction; hypertension; and renal insufficiency. Hepatic fibrosis is an associated extrarenal problem that results in significant morbidity in young children and adolescents. Treatment includes supportive care, dialysis, and renal transplantation. Acquired cysts (solitary/simple) are commonplace in older persons. Multiple cysts may be seen in association with potassium deficiency, congenital disorders, metabolic diseases, and toxic renal injury.(ABSTRACT TRUNCATED AT 400 WORDS)

Spontaneous carotid-jugular fistula and carotid dissection in a patient with multiple intracranial arachnoid cysts and hemifacial atrophy: a generalized connective tissue disorder? Case report

The authors report a case of a 45-year-old woman with pulsatile tinnitus who was found to have an unusual spontaneous fistula between the petrous internal carotid artery and internal jugular vein. The fistula resolved spontaneously, possibly related to daily manual compression of the ipsilateral common carotid artery. The patient also had a contralateral carotid artery dissection, multiple intracranial arachnoid cysts, and hemifacial atrophy. Her medical history was significant for easy bruisibility, abnormal scarring, and mitral valve prolapse. This association appears unique and may represent a previously underscribed generalized connective tissue disorder.