Myxoid degeneration of the aortic valve and isolated severe aortic regurgitation

Contemporary Valvular Mechanisms of Aortic Regurgitation in Tricuspid Aortic Valves: Importance in Repair Versus Replacement Strategy

BACKGROUND

This study was performed to determine cusp causes of aortic regurgitation in patients with tricuspid aortic valves without significant aortic dilatation and define cusp pathologies amenable to surgical repair (aortic valve repair [AVr]) versus aortic valve replacement.

METHODS AND RESULTS

We retrospectively reviewed surgical reports of consecutive adults with tricuspid aortic valves undergoing surgery for clinically significant aortic regurgitation within a prospective registry from January 2005 to September 2019. Valvular mechanisms were determined by systematic in vivo intraoperative quantification methods. Of 516 patients, 287 (56%) underwent repair (AVr; mean±SD age, 59.9±12.4 years; 81% men) and 229 (44%) underwent replacement (aortic valve replacement; mean±SD age, 62.8±13.8 years [P=0.01 compared to AVr]; 67% men). A single valvular mechanism was present in 454 patients (88%), with cusp prolapse (46%), retraction (24%), and perforation (18%) being the most common. Prolapse involved the right cusp in 86% of cases and was more frequent in men (P<0.001). Two-dimensional transesophageal echocardiography accuracy for predicting mechanisms was 73% to 82% for the right cusp, 55% to 61% for the noncoronary cusp, and 0% for the left-coronary cusp. Cusp prolapse, younger age, and larger patient size were associated with successful AVr (all P<0.03), whereas retraction, perforation, older age, and concomitant mitral repair were associated with aortic valve replacement (all P<0.03).

CONCLUSIONS

Right cusp prolapse is the most frequent single valvular mechanism in patients with tricuspid aortic valve aortic regurgitation, followed by cusp retraction and perforation. The accuracy of 2-dimensional transesophageal echocardiography is limited for left and noncoronary cusp mechanistic assessment. Prolapse is associated with successful AVr, whereas retraction and perforation are associated with aortic valve replacement. With systematic intraoperative quantification methods and current surgical techniques, more than half of tricuspid aortic valve aortic regurgitation cases may be successfully repaired.

Autoimmune connective tissue diseases and aortic valve replacement outcomes: a population-based study

Aims

Patients with autoimmune connective tissue diseases (CTDs) have a high burden of valvular heart disease and are often thought of as high surgical risk patients.

Methods and results

Patients undergoing aortic valve replacement (AVR) were identified in the Nationwide Readmissions Database between January 2012 and December 2018. Patients with a history of systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, mixed C, Sjögren syndrome, polymyositis, and dermatomyositis were included in the CTD cohort. Patients undergoing coronary artery bypass grafting concomitantly with AVR were excluded. A total of 569 600 hospitalizations were included, of which16 531 (2.9%) had CTD. CTD patients were more likely to be females, with higher rates of heart failure, pulmonary hypertension, and more likely to be insured by Medicare. CTD patients had lower mortality than non-CTD patients [odds ratio (OR) 0.66; 95% confidence interval (CI): 0.59–0.74] and stroke [OR 0.87; 95% (CI): 0.79–0.97]. CTD patients undergoing SAVR had lower mortality [OR 0.69; 95% (CI): 0.60–0.80] and stroke [OR 0.86; 95% (CI): 0.75–0.98). CTD patients undergoing TAVR had lower mortality outcomes [OR 0.67; 95% (CI): 0.56–0.80]; however, they had comparable stroke outcomes [OR 0.97; 95% (CI): 0.83–1.13, P = 0.69].

Conclusions

Outcomes for patients with CTD requiring AVR are not inferior to their non-CTD counterparts. A comprehensive heart team selection of patients undergoing AVR approaches should place CTD history under consideration; however, pre-existing CTD should not be prohibitive of AVR interventions.

Age-related etiologies of aortic regurgitation with moderate or greater severity and coronary cusp bending: evaluation using transesophageal echocardiography

PURPOSE

The prevalence of valvular heart disease has been rising, especially among those ≥ 65 years of age, because of age-related valvular degeneration resulting in an increase in the number of patients diagnosed with aortic regurgitation (AR). We analyzed transesophageal echocardiography (TEE) images in AR patients to identify the etiologies and investigate any differences in them according to age.

METHODS

We studied 146 consecutive patients with chronic moderate or severe AR who underwent TEE. AR etiology was evaluated based on the TEE images in all the patients, as well as in each group separated by age.

RESULTS

The total number of patients eligible was 126 (mean age 67 ± 12 years), consisting of an older group (n = 85, mean age 74 ± 5 years) and younger group (n = 41, mean age 52 ± 11 years). In total, the most common etiology of AR was cusp bending (33.0%). In the older group, it was the most frequent as well (48.2%), with the right coronary cusp being the most commonly affected site (90.2%). In the younger group, bicuspid aortic valve was the most common (36.5%). Subsequently, all the study subjects were re-classified into two groups according to the presence/absence of cusp bending. Multivariate analysis revealed that age was the only factor associated with cusp bending.

CONCLUSION

Cusp bending was the most frequent etiology of AR in the elderly. Preoperative detection of cusp bending by TEE would expand the therapeutic strategy for AR, including aortic valvuloplasty.

Non-dissecting large thoracic aortic aneurysm leading to chronic aortic insufficiency presenting as acute heart failure

Large, non-dissecting thoracic aortic aneurysms (TAA) up to 13 cm in size are typically found in elderly patients with non-specific respiratory symptoms yet must be detected quickly due to their mortality risk. We present a 31-year-old man with exertional dyspnea secondary to aortic insufficiency from a 9.4 cm TAA.

A Novel Ex Vivo Model of Aortic Valve Calcification. A Preliminary Report

Background: No pharmacological treatment exists to prevent or stop the calcification process of aortic valves causing aortic stenosis. The aim of this study was to develop a robust model of induced calcification in whole aortic valve leaflets which could be suitable for studies of the basic mechanisms and for testing potentially inhibitory drugs.

Methods: Pig hearts were obtained from a commercial abattoir. The aortic valve leaflets were dissected free and randomized between experimental groups. Whole leaflets were cultured in individual wells. Two growth media were used for cultivation: standard growth medium and an antimyofibroblastic growth medium. The latter was employed to inhibit contraction of the leaflet into a ball-like structure. Calcification was induced in the growth medium by supplementation with an osteogenic medium. Leaflets were cultivated for four weeks and medium was changed every third day. To block calcification, the inhibitor SNF472 (a formulation of the hexasodium salt of myo-inositol hexaphosphate hexasodium salt) was used at concentrations between 1 and 100 µM. After cultivation for four weeks the leaflets were snap frozen in liquid nitrogen and kept at −80 °C until blind assessment of the calcium amount in leaflets by inductively coupled plasma optical emission spectroscopy. For statistical analysis, a Kruskal–Wallis test with Dunn’s post-test was applied.

Results: Osteodifferentiation with calcium accumulation was in principle absent when standard medium was used. However, when the antimyofibroblastic medium was used, a strong calcium accumulation was induced (p = 0.006 compared to controls), and this was blocked in a dose-dependent manner by the calcification inhibitor SNF472 (p = 0.008), with an EC₅₀ of 3.3 µM.

Conclusion: A model of experimentally induced calcification in cultured whole leaflets from porcine aortic valves was developed. This model can be useful for studying the basic mechanisms of valve calcification and to test pharmacological approaches to inhibit calcification.

Pathology of the Aortic Valve: Aortic Valve Stenosis/Aortic Regurgitation

PURPOSE OF REVIEW

This discussion is intended to review the anatomy and pathology of the aortic valve and aortic root region, and to provide a basis for the understanding of and treatment of the important life-threatening diseases that affect the aortic valve.

RECENT FINDINGS

The most exciting recent finding is that less invasive methods are being developed to treat diseases of the aortic valve. There are no medical cures for aortic valve diseases. Until recently, open-heart surgery was the only effective method of treatment. Now percutaneous approaches to implant bioprosthetic valves into failed native or previously implanted bioprosthetic valves are being developed and utilized. A genetic basis for many of the diseases that affect the aortic valve is being discovered that also should lead to innovative approaches to perhaps prevent these disease. Sequencing of ribosomal RNA is assisting in identifying organisms causing endocarditis, leading to more effective antimicrobial therapy. There is exciting, expanding, therapeutic innovation in the treatment of aortic valve disease.

Isolated myxoid degeneration of aortic valve: diagnostic dilemma

Myxoid degeneration of the aortic valve as a cause of acute aortic valve regurgitation in young age is uncommon. We report a 39-year-old African-American man with a history of epilepsy and hypertension who presented with a 1-month history of worsening shortness of breath. He was diagnosed with acute pulmonary oedema. Transoesophageal echocardiogram showed normal ejection fraction but severe aortic valve insufficiency with small masses on the ventricular side of the right and non-coronary cusps, small vegetations cannot be ruled out but other valves were normal. Subsequent cultures were negative for endocarditis. Myocardial positron emission tomography (PET) scan was strongly suggestive of cardiac sarcoidosis. However, this diagnosis was ruled out as well when he underwent aortic valve replacement with bioprosthetic valve as he did not want to take long-term anticoagulation. Histological examination of the aortic valve showed myxoid degeneration. The patient was doing very well 1 year after the surgery.

Aortic valve repair update

The key for successful valve repair is full understanding of the regurgitant mechanism and sufficient evaluation of the valve. Currently, multidetector computed tomography has been introduced for evaluation. The aortic valve can be analyzed in details preoperatively. The main causes of aortic regurgitation (AR) in the adult population are degenerative leaflet change and annulus dilatation. Restoration to normal structure can be accomplished mainly by plication. Central leaflet plication near the Arantius nodule is a simple technique for redundant tissue. For leaflet deficiency, pericardial patch plasty may be an option. No universal technique exists for plication of the aortic annulus. The valve-sparing aortic root replacement firmly stabilizes the ventriculo-aortic junction (VAJ) and assures repair durability even in patients with mild to moderate root dilatation. Subcommissural annuloplasty (Cabrol stitch) does not seem sufficient for the prevention of VAJ dilatation. Circumferential annuloplasties may have a greater potential. However, convenient device for annular plication is still in development. The bicuspid aortic valve is a congenital heart valve lesion. A basic technique is free margin plication of the fused leaflet. Aortic root dilatation may contribute to AR severity. Valve-sparing aortic root replacement may improve repair durability. Considering the great advances in valve repair, young patients with AR should be informed that valve repair is a promising option for surgical treatment.

Giant fenestration and fibrous strand rupture of aortic valve without massive regurgitation

We present a case of a giant fenestration and a fibrous strand rupture of the aortic valve without massive regurgitation. A 56-year-old woman, was referred for coronary revascularization, had II-III degree aortic regurgitation without symptoms of heart failure. On the intraoperative direct view, the non coronary cusp (NCC) had the giant fenestration and the left coronary cusp (LCC) had the fibrous strand rupture. There was no severe inflammation, thrombi, or vegetation. Finally, she had coronary artery bypass surgery and aortic valve replacement. Although fenestration of the aortic valve is not rare, it is hard to determine its configuration preoperatively. When the echocardiographic findings indicate an eccentric regurgitation flow despite the absence of prolapse, we should perform examinations with the possibility of coexisting aortic valve fenestration in mind. Massive regurgitation does not necessarily correspond to a giant fenestration and a fibrous strand rupture. We report a rare case of the unusually large fenestration and the rupture of the fenestrated fibrous strand of the aortic valve without massive regurgitation.

Cleft-like formation of the aortic valve in an adult patient with a single coronary artery

A 51-year-old woman was admitted to our hospital with heart failure due to aortic regurgitation. Examination showed severe aortic regurgitation mainly due to cleft-like deformity of the right coronary cusp and single coronary artery. Aortic valve replacement was performed, and the deformity was seen in all aortic cusps. Histological study showed elongation of the leaflets by myofibrotic and fibrotic hyperplasia without calcification and inflammation in the aortic valve. This deformity likely arose from an acquired modification of a congenitally malformed aortic valve.

Peripartum presentation of an acute aortic dissection

We report the case of an acute type A aortic dissection occurring in a 35-year-old parturient. The initial diagnosis was missed; a subsequent emergency Caesarean section 3 weeks after presentation was followed by the development of left ventricular failure and pulmonary oedema in the early postoperative period. Echocardiography confirmed the diagnosis of aortic dissection and the patient underwent a successful surgical repair.

Pathogenetic Significance of Myxomatous Degeneration in Fenestration-Related Massive Aortic Regurgitation

BACKGROUND

Aortic valvular regurgitation has several mechanisms and the present study investigated its clinicopathological correlations with aortic valve fenestration.

METHODS AND RESULTS

Six male patients with massive regurgitation and enlarged fenestrations or ruptured fenestrated fibrous cords underwent aortic valve replacement. The clinicopathological features showed many similarities. Four cases had family histories of aortic regurgitation. All six patients showed moderate to severe myxomatous degeneration of the aortic valve and enlargement of aortic annulus. Four patients had 1-2 ruptured fibrous cords, located at the right coronary cusp. Echocardiographic examinations showed an abnormal fibrous cord attached to the prolapsing cusp in 3 cases with ruptured fenestrated valve and detailed examination by transesophageal echocardiography showed an intact fenestrated fibrous cord at the commissure in 1 case.

CONCLUSION

Extensively fenestrated cusps with an enlarged aortic annulus because of myxomatous degeneration can cause chronic regurgitation or sudden deterioration after rupture of the fibrous cord. There is an increasing incidence of fenestration-related aortic regurgitation in the Japanese population. An important pathogenetic factor in male patients is myxomatous degeneration of the aortic cusp and annulus.

Floppy aortic valves without aortic root dilatation: clinical, histologic, and ultrastructural studies

Gross anatomic, histologic and ultrastructural studies were made on 32 floppy aortic valves (FAVs) resected at the time of aortic valvular replacement for aortic regurgitation. Patients with the FAVs had relatively long clinical courses and had severe aortic regurgitation with mild symptoms of heart failure. The sizes of the mechanical valves implanted in the patients with FAVs were not large, indicating that the aortic regurgitation in these patients was not worsened by dilatation of the aortic ring. Two types of FAVs were recognized grossly, according to whether they showed abnormal cuspal thickening or thinning. Accumulations of myxoid material in the spongiosa were found in all FAVs, regardless of cuspal gross morphology. Histologically, the collagen fibers were sparse and irregularly arranged and elastic fibers were disrupted and finely granular in the myxomaotus areas of FAVs. Ultrastructurally, the myxomatous material consisted of numerous star-shaped proteoglycan granules associated with spiraling collagen fibrils and abnormal elastic fibers. Numerous spiraling collagen fibrils were observed especially at the border area of myxomatous change that extended from the spongiosa into the fibrosa. Abnormal elastic fibers had either a granular appearance of their amorphous components without microfibrils, or irregularly arranged masses of microfibrils without amorphous components. These abnormalities of connective tissue components, resulting from defective formation and/or increased degradation were similar to those in floppy mitral valves, and were related to the floppiness of cardiac valves.

Composite graft replacement after aortic valvuloplasty in Takayasu arteritis

A 24-year-old woman had undergone valvuloplasty of the aortic valve and external reinforcement of an aneurysm of the ascending aorta during the active phase of Takayasu arteritis 1 year prior to admission to our hospital. On examination, she was diagnosed as having a large false aneurysm of the ascending aorta with annuloaortic ectasia and severe aortic regurgitation, bilateral common carotid artery aneurysms with a left internal carotid artery saccular aneurysm, and bilateral subclavian artery and right vertebral artery obstructions due to Takayasu arteritis. Because of the risk of rupture, surgical intervention was carried out in spite of the fact that aortitis was in the active phase.

Two-dimensional echo Doppler findings in juvenile and adult onset ankylosing spondylitis with long-term disease

The authors' objective was to determine by 2-dimensional echo Doppler (2DECHO) the cardiac abnormalities in juvenile onset ankylosing spondylitis (JOAS) and adult onset ankylosing spondylitis (AOAS) in male patients with long-term disease. Twenty patients with JOAS, 31 with AOAS, and 20 healthy controls of the same age and gender without cardiopulmonary symptoms were studied. Using 2DECHO, the heart dimensions were determined according to American Society of Echocardiography guidelines. The left ventricle ejection fraction (LVEF) was calculated by Teichholz's formula. Cardiomyopathy was established when 2DECHO had diminished LVEF. Statistics used were the Student t and Fisher test, chi2, and ANOVA. Ninety percent of JOAS and 51% of AOAS patients were B27+ (p=0.005). The disease duration was 19.3 +/- 8.8 years in JOAS and 14.8 +/- 12.8 years in AOAS (p=NS). Age at the time of the study was 30.7 +/- 9.9 years in JOAS vs 40.3 +/- 12.7 in AOAS (p=0.003), and vs 40.2 +/- 17 years in controls (p=NS). There was a higher frequency of cardiomyopathy in AOAS (32.2%) than in JOAS (25%) and the controls (0%) (p=0.01). Patients with JOAS had a higher mitral valve gradient (25%) than AOAS patients (19%, p=NS) and controls (0%, p=0.04). Abnormal aortic ring reflectance was shown in 19% of AOAS vs 0% abnormalities in JOAS and controls (p=0.01). The aortic root diameter was increased in 58% of AOAS, 30% of JOAS, and 0% of controls (p=0.001). The frequency of 2DECHO abnormalities was increased in cardiopulmonary asymptomatic spondylitis patients. Despite the high frequency of B27+, JOAS had a lower frequency of aortic abnormalities than AOAS. Mitral valve gradient was found in JOAS and in AOAS that could contribute to a decreased ejection fraction and to left ventricular dysfunction.

Clinical characteristics of a familial inherited myxomatous valvular dystrophy mapped to Xq28

OBJECTIVES

The purpose of this study was to describe the phenotypic characteristics of an inherited myxomatous valvular dystrophy mapped to Xq28.

BACKGROUND

Myxomatous valve dystrophies are a frequent cause of valvular diseases, the most common being idiopathic mitral valve prolapse. They form a group of heterogeneous diseases difficult to subclassify. The first mapping of the gene for a myxoid valvular dystrophy to Xq28 allowed investigation of the phenotype of affected members in a large family and characterization of the disease.

METHODS

Among the 318 members in the pedigree, 89 agreed to participate in this study. Phenotypic characteristics were investigated using clinical examination, transthoracic echocardiography and biological analysis (F.VIII activity). Genetic status was based on haplotype analysis.

RESULTS

Among 46 males, 9 were hemizygous to the mutant allele and had an obvious mitral and/or aortic myxomatous valve defect, and 4 had undergone valvular surgery. All had typical mitral valve prolapse associated in six cases with moderate to severe aortic regurgitation. The valve defect cosegregated with mild hemophilia A (F.VIII activity = 0.32 +/- 0.05). The 37 remaining males had normal valves and normal F.VIII activity. Heterozygous women were identified on the basis of their haplotypes. Among the 17 women heterozygous to the mutant allele, moderate mitral regurgitation was present in 8, associated with mild mitral valve prolapse in 1 and aortic regurgitation in 3, whereas 2 women had isolated mild aortic regurgitant murmur. In heterozygotes, the penetrance value was 0.60 but increased with age.

CONCLUSION

X-linked myxomatous valvular disease is characterized by mitral valve dystrophy frequently associated with degeneration of the aortic valves affecting males and, to a lower severity, females. The first localization of a gene for myxomatous valvular diseases is the first step for the subclassification of these diseases.

Causes of isolated aortic insufficiency in an urban population in the 1990s a review of 56 surgical pathology cases

Until recently, the cause of isolated aortic insufficiency (AI) was usually thought to be inflammatory or rheumatic in most cases. However, at our institution we have noted a high prevalence of myxomatous degeneration (MD) in aortic valves removed for AI. In this study we report anatomic observations on valves from 56 consecutive patients with isolated AI undergoing aortic valve replacement surgery. Fifty-six consecutive aortic valves removed at our institution from 1994 to 1996 for isolated AI and/or aortic aneurysm were reviewed. Anatomic features were compared with clinical history and echocardiographic data. The anatomic results were also compared to 22 age-matched control aortic valves obtained at autopsy. In 13/56 cases (23%), a specific valvular cause of AI was determined (infectious endocarditis, seven cases; chronic rheumatic disease, four cases; congenital bicuspid valve, two cases). Of the remaining (idiopathic) 43 cases, 18 (42%) had severe isolated MD defined as >50% expansion of the spongiosa and disruption of the fibrosa by the deposition of acid mucopolysaccharides in the absence of severe calcification, fibrosis, or other pathologic findings. Only 1/22 aortic valves from the autopsy controls had severe MD. Eighteen of the 56 patients also had a clinical history of aortic dilatation/aneurysm of which 12 were confirmed to be dilated by echocardiographic criteria. Of these 12, five (42%) had MD of the aortic valve only, three (25%) had both MD and cystic medial degeneration (CMD) of the aorta, two (17%) had CMD of the aorta only, and two (17%) had no specific diagnosis. Isolated MD of the aortic valve is the most common cause of isolated AI in our patient population. Furthermore, in a subset of non-Marfan's patients with both AI and dilatation of the aortic root/aortic aneurysm the incidence of MD is even higher (67%). These results suggest that there is overlap between MD and CMD in non-Marfan's patients and that both entities may be part of a spectrum of a generalized connective tissue disorder.

Mucoid dysplasia of tricuspid and congenital bicuspid aortic valves in Syrian hamsters (Mesocricetus auratus)

A histological study was made of the aortic valves of 141 Syrian hamsters aged between 35 and 657 days, belonging to an inbred laboratory colony with a high incidence of congenital bicuspid aortic valves. A tricuspid aortic valve was found in 81 specimens, whereas the remaining 60 possessed a bicuspid aortic valve. In all bicuspid valves there were two aortic sinuses, a ventral and a dorsal, each supporting one cusp. Thirty-three (23.4%) of the 141 specimens showed mucoid dysplasia of the aortic valve. The defect was characterized by thickening of the valve cusps and disruption of the fibrosa layer accompanied by an increased amount of glycosaminoglycans. Ten (12.3%) of the 81 tricuspid aortic valves and 23 (38.3%) of the 60 bicuspid aortic valves were dysplastic. This difference was statistically significant (P < 0.001). The findings indicate that, in the Syrian hamster, the simultaneous occurrence of bicuspid aortic valve and aortic valve dysplasia is not a random event. However, the fact that these valve defects also occur independently suggests that there is no primary morphogenetic dependence between them, but that some other cause predisposes to their concurrence.

Non-inflammatory aortic root disease and floppy aortic valve as cause of isolated regurgitation: a clinico-morphologic study

A clinico-morphologic study was performed on 1120 patients who underwent aortic valve replacement at the Department of Medical and Surgical Cardiology, 2nd University Medical School of Naples, Naples, Italy, from January 1981 through December 1991. In 69 cases the aortic valve was incompetent due to a non-inflammatory aortic root disease such as myxomatous infiltration of the cusps and or aortic root dilatation. Among these patients males were prevalent (male/female ratio = 2.2). The mean age was 37 +/- 7.5 years. A floppy mitral valve was diagnosed in 16 cases while in one a left atrial myxoma was found. The patients were divided into 3 groups: Group 1-29 patients with aortic root dilatation and normal cusps; Group 2-25 patients with aortic root dilatation and myxomatous infiltration of aortic cusps (floppy aortic valve); and Group 3-15 patients with floppy aortic valve and undilated aortic root. At the gross examination the cusps of the patients in Groups 2 and 3 were redundant, thin, soft and gelatinous. The histology showed myxomatous infiltration with disruption of the fibrous layer. In patients with aortic root dilatation the histology of the aortic root fragments showed a cystic medial necrosis. Deep correlation was found between the root dilatation and the grade of aortic wall cystic medial necrosis. Cusp's diastasis was the cause of aortic regurgitation in patients with aortic root dilatation, while cusp prolapse caused aortic incompetence in presence of the floppy aortic valve and undilated aortic root.(ABSTRACT TRUNCATED AT 250 WORDS)

The clinical and pathological features of isolated aortic regurgitation in relation to its etiology

Chronic isolated aortic regurgitation (AR) caused by degenerative, rheumatic, and Marfan etiologies were compared in a study of 87 patients. There were three hospital deaths in the Marfan group, but none in the rheumatic and degenerative groups. The late postoperative survival rates at 5 and 10 years were 98% and 94%, respectively, in the rheumatic group; 84% and 84%, respectively, in the degenerative group; and 85% and 78%, respectively, in the Marfan group. An analysis of the late complications disclosed a higher incidence of aortic dissection and paravalvular leakage in the degenerative and Marfan groups than in the rheumatic group. In the degenerative group, 4 of the 32 patients developed acute aortic dissection within 3 years following aortic valve replacement. The aortic root diameter in these 4 patients was more than 40 mm at the time of surgery, whereas it was less than 40 mm in the remaining 28 patients. In conclusion, considering the progressive nature of myxomatous degeneration, patients with a severely dilated aortic root diameter should be monitored carefully with echocardiography after surgery.

Pathology of aortic valve stenosis and pure aortic regurgitation: a clinical morphologic assessment--Part II

This two-part article examines the histologic and morphologic basis for stenotic and purely regurgitant aortic valves. Part I discussed stenotic aortic valves and Part II discusses causes of purely regurgitant aortic valves. In over 95% of stenotic aortic valves, the etiology is one of three types: congenital (primarily bicuspid), degenerative, and rheumatic. Other rare causes included active infective endocarditis, homozygous type II hyperlipoproteinemia, and systemic lupus erythematosis. The causes of pure aortic regurgitation are multiple but can be separated into diseases affecting the valve (normal aorta) (infective endocarditis, congenital bicuspid, rheumatic, floppy), diseases affecting the walls of aorta (normal valve) (syphilis, Marfan's dissection), disease affecting both aorta and valve (abnormal aorta, abnormal valve) (ankylosing spondylitis), and disease affecting neither aorta nor valve (normal aorta, normal valve) (ventricular septal defect, systemic hypertension). Diseases affecting the aortic valve alone are the most common subgroup of conditions producing purely regurgitant aortic valves.

Aortic valve prolapse with aortic regurgitation assessed by Doppler color-flow echocardiography

The incidence of and the Doppler color-flow echocardiographic characteristics of aortic valve prolapse with nonrheumatic aortic regurgitation were examined. Aortic valve prolapse was observed in 21 of 243 patients (15 men and 6 women) with aortic regurgitation as detected by Doppler color-flow echocardiography (rheumatic, 112; nonrheumatic, 131) in 1247 consecutive patients. Patients with aortic valve prolapse included three patients with essential hypertension and one with annuloaortic ectasia. The remaining 17 patients (7% of those with aortic regurgitation) had no other associated cardiovascular disease (idiopathic aortic valve prolapse). Prolapse of the mitral or the tricuspid valve or both was associated with aortic valve prolapse in seven patients. Aortic regurgitation jet was markedly deviated from the axis of left ventricular outflow tract toward the anterior mitral leaflet or the interventricular septum in 17 of 21 (81%) patients with aortic valve prolapse, whereas 28 of 110 (25%) patients with nonrheumatic aortic regurgitation without prolapse and 17 of 112 (15%) patients with rheumatic aortic regurgitation without prolapse showed the deviation of regurgitant jet (p < 0.001). In conclusion, idiopathic aortic valve prolapse is one of the significant causes of aortic regurgitation, and a marked deviation of regurgitant jet is a characteristic Doppler color-flow echocardiographic finding of aortic regurgitation that results from aortic valve prolapse.

The Marfan syndrome: cardiovascular physical findings and diagnostic correlates

Correlations among cardiac symptoms and auscultatory and phonoechocardiographic findings in Marfan syndrome have not been completely defined. A total of 24 patients with Marfan syndrome (16 men and 8 women; mean age 28.2 +/- 8.6 years) were studied. Mitral valve prolapse was noted in 22, of whom 19 had either nonejection systolic click or mitral regurgitation murmur. Mitral regurgitation was noted in 12 patients by Doppler imaging. Aortic root dilatation was noted in 20 patients and aortic regurgitation in six, five of whom had aortic regurgitation murmur (5 of 20 patients had undergone surgery). Proximal aortic dissection was noted in two. Dyspnea (n = 12) was associated with progressive mitral or aortic regurgitation in four, but in the others dyspnea could not be explained by valvular or ventricular abnormalities. Chest pain was related to pneumothorax in five and aortic dissection in two but was not associated with either in 15 patients. Palpitations (n = 12) and lightheadedness (n = 6) were not associated with specific arrhythmias. In conclusion, mitral valve prolapse and aortic root dilatation were the most common cardiovascular abnormalities in Marfan syndrome. Mitral valve prolapse was frequently associated with typical auscultatory findings and symptoms including dyspnea, chest pain, palpitations, and lightheadedness, whereas aortic root dilatation could be clinically silent unless complicated by aortic regurgitation or aortic dissection.

Hypertension in aortic valve disease and its response to valve replacement

We have investigated the prevalence of hypertension and the response of blood pressure to operation in 87 patients with lone aortic valve disease who underwent aortic valve replacement. In patients with aortic stenosis alone 26% were hypertensive pre-operatively (age and sex adjusted blood pressure greater than 160 systolic and or greater than 95 mmHg diastolic) and 24% were hypertensive post-operatively. In those with aortic regurgitation alone, hypertension was present in 65% before and 57% after valve replacement using the same criterion. For combined stenosis and regurgitation, the prevalence was 54% and 62%, respectively. The post-operative increase in systolic pressure in patients with aortic stenosis occurred mainly in those with a history of left ventricular failure. In those with aortic regurgitation or combined stenosis with regurgitation, diastolic pressure rose after valve replacement resulting in a prevalence of diastolic hypertension of 44% and 35%, respectively. Blood pressure changes were not predicted by the type of valve inserted nor its size. Our data show that despite severe symptomatic aortic valve disease, systolic hypertension was common in aortic stenosis and diastolic hypertension was found in aortic regurgitation. This underlines the importance of blood pressure monitoring in patients following aortic valve replacement.

Rare or unusual causes of chronic, isolated, pure aortic regurgitation

Six patients undergoing aortic valve replacement had rare or unusual causes of isolated, pure aortic regurgitation. Two patients had congenitally bicuspid aortic valves with a false commissure (raphe) displaced to the aortic wall ("tethered bicuspid aortic valve"), two had floppy aortic valves, one had a congenital quadricuspid valve, and one had radiation-induced valve damage.

HLA-B27: an important genetic risk factor for lone aortic regurgitation and severe conduction system abnormalities

PURPOSE

HLA-B27, an immunogenetic marker that is present in 8 percent of the white population around the world, has been found to be an important risk factor for the development of a group of rheumatic disorders, the seronegative spondyloarthropathies. Our objective was to assess the possible role of HLA-B27 and the associated inflammatory disease process in the development of lone aortic regurgitation.

PATIENTS AND METHODS

A group of 91 patients with lone aortic regurgitation were studied by HLA typing and clinical and roentgenologic examination.

RESULTS

The HLA-B27-associated inflammatory disease process was found to be the probable underlying cause in 15 to 20 percent of patients with lone aortic regurgitation of different degrees of severity. Furthermore, HLA-B27 was found in 88 percent of the male patients with the combination of aortic regurgitation and severe conduction system abnormalities.

CONCLUSION

We suggest that this cardiac syndrome should be regarded as an HLA-B27-associated syndrome, sometimes part of ankylosing spondylitis or Reiter's disease, but just as often presenting without obvious rheumatic disease. The marker is thus an important and widely distributed risk factor not only for the development of rheumatic disease but also for acquired aortic regurgitation and sever conduction system abnormalities.

The aetiology and course of isolated severe aortic regurgitation: a clinical, pathological, and echocardiographic study

Seventy two consecutive patients with severe isolated aortic regurgitation were evaluated by preoperative echocardiographic and angiographic assessment of the aortic root. Biopsy specimens of the aortic wall were taken at operation. Two major groups of patients were found: those with cusp derangement but normal aortic roots and those with normal cusps but dilated aortic roots. Of the 42 cases of abnormal cusps, 20 were rheumatic, 15 were infective, and six were bicuspid. One patient had a tear in an otherwise normal cusp. Of the 30 cases of abnormal roots but normal cusps, six had inflammatory changes (syphilis, Reiter's disease, giant cell aortitis) and 24 had root dilatation caused by non-inflammatory destruction of elastic laminae. Echocardiographic measurement of the aorta at the level of the top of the commissures predicted the findings at pathology. In 37 of 39 patients with cusp disease the measurement was less than 37 mm. In 27 of 33 patients with root disease the measurement was greater than or equal to 37 mm. This difference was statistically significant. There was no difference in the sizes of the prosthesis used in each group, suggesting that it was the diameter of the junction of the aorta with the sinuses rather than the junction of the sinuses with the ventricle that was important in aortic regurgitation. Clinical progression in patients with non-inflammatory aortic root disease is slower than in patients with infective disease but faster than in those with rheumatic cusp disease.

Postinflammatory mitral and aortic valve prolapse: a clinical and pathological study

In this study we reevaluated whether the sole cause of mitral valve prolapse (MVP) and aortic valve prolapse (AVP) is myxomatous degeneration. Forty-two surgical cases of prolapsed valves with mitral and/or aortic regurgitation were reviewed (AVP in nine, MVP in 27, and combined AVP and MVP [CVP] in six). On microscopic examination, myxomatous degeneration was observed in 20 patients, including six with AVP, 13 with MVP, and one with CVP. In the other 22 patients, including three with AVP, 14 with MVP, and five with CVP, microscopic examination revealed fibrosis with vascularization and scattered infiltration of inflammatory round cells caused by postinflammatory changes with or without chronic inflammation. We coined the term "postinflammatory valve prolapse" (PIVP) to describe these valves. Both postinflammatory and myxomatous degeneration were observed in seven patients with floppy mitral valves attributable to PIVP. Rupture of chordae tendineae was present in six patients with myxomatous mitral valve and three with PIVP. Seven patients with PIVP had a history of rheumatic fever. The results suggest that valvular prolapse is produced not only by myxomatous degeneration but also by postinflammatory changes, including those caused by rheumatic fever.

Cardiovascular disease of connective tissue origin

Inherited abnormalities of connective tissue elements often cause changes in the structure and function of the cardiovascular system. Well-known heritable disorders of connective tissue in which cardiovascular abnormalities are prominent include the Marfan syndrome and the Ehlers-Danlos syndrome. Connective tissue abnormalities also occur without the associated features of a recognized syndrome. These include isolated valvular prolapse and anuloaortic ectasia. In this review, the cardiovascular features of connective tissue abnormalities--both the recognized syndromes and the isolated abnormalities--are described, important concepts in the diagnosis and treatment of these disorders are reviewed, and the classification of inherited connective tissue abnormalities of the cardiovascular system is discussed.