Ten-year clinical laboratory follow-up after application of a symptom-based therapeutic strategy to patients with severe chronic aortic regurgitation of predominant rheumatic etiology

OBJECTIVES

This study was designed to assess the feasibility and the long-term results of a symptom-based strategy of aortic valve replacement in a Brazilian population with predominant rheumatic etiology.

BACKGROUND

Optimal criteria for valve replacement in aortic regurgitation (AR) are still not entirely clear. The appearance of symptoms is an indication for surgery, but may be associated with myocardial damage. Although cardiac imaging data have provided a safer guide for such decisions, the use of symptom-based surgical indication has not been validated and might conceivably be better in populations with predominant rheumatic etiology and younger age.

METHODS

Echocardiography and rest-exercise radionuclide ventriculography were performed in 75 patients with severe AR, age 28 +/- 9 years, over a period of 10 +/- 0.69 years. Thirty-seven patients developed symptoms and underwent aortic valve replacement surgery within six months. Thirty-eight patients remained asymptomatic and were managed medically.

RESULTS

Survival was 100% in asymptomatic patients and 82% in symptomatic. Surgical treatment caused marked ventricular remodeling, with ventricular diameter involution and an improvement of rest-exercise ejection fraction percent variation. Multivariate analysis showed that the probability of developing symptoms within 10 years was 58% for a patient with a left ventricular end-diastolic diameter > or =70 mm and 76% for a patient with left ventricular end-systolic (LVESD) > or =50 mm. Logistic regression identified LVESD and age as the most predictive and specific, but not sensitive, indicators of symptom development.

CONCLUSIONS

Application of a standardized therapeutic strategy to patients with severe AR and predominant rheumatic etiology resulted in 90.6% survival after 10 years of follow-up.

Contrast-enhanced magnetic resonance imaging identifies focal regions of intramyocardial fibrosis in patients with severe aortic valve disease: Correlation with quantitative histopathology

BACKGROUND

Chronic aortic valve disease (AVD) is characterized by progressive accumulation of interstitial myocardial fibrosis (MF). However, assessment of MF accumulation has only been possible through histologic analyses of endomyocardial biopsies. We sought to evaluate contrast-enhanced magnetic resonance imaging (ce-MRI) as a noninvasive method to identify the presence of increased MF in patients with severe AVD.

METHODS

Seventy patients scheduled to undergo aortic valve replacement surgery were examined by cine and ce-MRI in a 1.5-T scanner. Cine images were used for the assessment of left ventricular (LV) volumes, mass, and function. Delayed-enhancement images were used to characterize the regions of MF. In addition, histologic analyses of myocardial samples obtained during aortic valve replacement surgery were used for direct quantification of interstitial MF. Ten additional subjects who died of noncardiac causes served as controls for the quantitative histologic analyses.

RESULTS

Interstitial MF determined by histopathologic analysis was higher in patients with AVD than in controls (2.7% +/- 2.0% vs 0.6% +/- 0.2%, P = .001). When compared with histopathologic results, ce-MRI demonstrated a sensitivity of 74%, a specificity of 81%, and an accuracy of 76% to identify AVD patients with increased interstitial MF. There was a significant inverse correlation between interstitial MF and LV ejection fraction (r = -0.67, P < .0001). Accordingly, patients with identifiable focal regions of MF by ce-MRI exhibited worse LV systolic function than those without MF (45% +/- 14% vs 65% +/- 14%, P < .0001).

CONCLUSIONS

Contrast-enhanced MRI allows for the noninvasive detection of focal regions of MF in patients with severe AVD. Moreover, patients with identifiable MF by ce-MRI exhibited worse LV functional parameters.

Influence of the maze procedure on the treatment of rheumatic atrial fibrillation - evaluation of rhythm control and clinical outcome in a comparative study

OBJECTIVE

The aim of this study was to evaluate the influence of the maze procedure on the treatment of rheumatic atrial fibrillation in patients with mitral valve disease.

METHODS

Fifty-five patients (mean age 51 years; 47 females) with rheumatic mitral valve disease and associated atrial fibrillation in New York Heart Association functional class III or IV, preoperatively, were operated upon. Thirty-five had double dysfunction, 19 had stenosis, and one had mitral regurgitation. None had other associated heart diseases or previous operations. The patients were divided into two groups: GI, 20 patients were treated for mitral valve disease with associated maze procedure; GII, 35 patients were treated for mitral valve disease without the maze procedure. The preoperative echocardiogram showed a left atrial diameter in GI of 5.35 mm and in GII of 5.57 mm (P=0.779). The groups were considered clinically similar (P=0.759). Cardiopulmonary bypass was used in all patients. The mitral valve was replaced with a biological prosthesis in 24 patients and repaired in 31 patients.

RESULTS

Three hospital deaths occurred, one in GI, two in GII. After cardiopulmonary bypass, 37.1% of patients in GII remained in atrial fibrillation. All patients in GI recovered regular rhythm (P<0.0001). In the ICU, atrial fibrillation was detected in 80% of patients in GII and maintained in 76.4% in a mean follow-up period of 38.5 months. In GI, atrial fibrillation occurred in 20% of patients in the ICU and maintained in 5.3% in 41 months of mean follow-up (P=0.0001). None of the patients in GI and 20.6% of patients in GII had a thromboembolic episode 1-63 months after the operation (P=0.041). Four late deaths occurred (two in each group), two being due to progression of valvular disease, one after an episode of pulmonary infection and one with no cardiac cause.

CONCLUSION

The maze procedure is effective in treating atrial fibrillation in patients with rheumatic mitral valve disease. The results are sustained in the mid-term follow-up period, preventing postoperative thromboembolic episodes, and with acceptable morbidity and mortality.

Comparison of inhaled nitric oxide versus oxygen on hemodynamics in patients with mitral stenosis and severe pulmonary hypertension after mitral valve surgery

Pulmonary hypertension represents an important cause of morbidity and mortality in patients with mitral stenosis who undergo cardiac surgery, especially in the postoperative period. The aim of this study was to test the hypothesis that inhaled nitric oxide (iNO) would improve the hemodynamic effects and short-term clinical outcomes of patients with mitral stenosis and severe pulmonary hypertension who undergo cardiac surgery in a randomized, controlled study. Twenty-nine patients (4 men, 25 women; mean age 46 ± 2 years) were randomly allocated to receive iNO (n = 14) or oxygen (n = 15) for 48 hours immediately after surgery. Hemodynamic data, the use of vasoactive drugs, duration of stay, and short-term complications were assessed. No differences in baseline characteristics were observed between the groups. After 24 and 48 hours, patients receiving iNO had a significantly greater increase in cardiac index compared to patients receiving oxygen (p <0.0001). Pulmonary vascular resistance was also more significantly reduced in patients receiving iNO versus oxygen (-117 dyne/s/cm(5), 95% confidence interval -34 to -200, vs 40 dyne/s/cm(5), 95% confidence interval -34 to 100, p = 0.005) at 48 hours. Patients in the iNO group used fewer systemic vasoactive drugs (mean 2.1 ± 0.14 vs 2.6 ± 0.16, p = 0.046) and had a shorter intensive care unit stay (median 2 days, interquartile range 0.25, vs median 3 days, interquartile range 7, p = 0.02). In conclusion, iNO immediately after surgery in patients with mitral stenosis and severe pulmonary hypertension improves hemodynamics and may have short-term clinical benefits.

The Role of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnosis of Left-sided Endocarditis: Native vs Prosthetic Valves Endocarditis

BACKGROUND

18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) has emerged as a useful diagnostic tool for suspected infective endocarditis (IE) in patients with prosthetic valves or implantable devices. However, there is limited evidence regarding use of 18F-FDG-PET/CT for the diagnosis of native valve endocarditis (NVE).

METHODS

Between 2014 and 2017, 303 episodes of left-sided suspected IE (188 prosthetic valves/ascending aortic prosthesis and 115 native valves) were studied. 18F-FDG-PET/CT accuracy was determined in the subgroups of patients with NVE and prosthetic valve endocarditis (PVE)/ascending aortic prosthesis infection (AAPI). Associations between inflammatory infiltrate patterns and 18F-FDG-PET/CT uptake were investigated in an exploratory ad hoc histological analysis.

RESULTS

Among 188 patients with PVE/AAPI, the sensitivity, specificity, and positive and negative predictive values of 18F-FDG-PET/CT focal uptake were 93%, 90%, 89%, and 94%, respectively, while among 115 patients with NVE, the corresponding values were 22%, 100%, 100%, and 66%. The inclusion of abnormal 18F-FDG cardiac uptake as a major criterion at admission enabled a recategorization of 76% (47/62) of PVE/AAPI cases initially classified as "possible" to "definite" IE. In the histopathological analysis, a predominance of polymorphonuclear cell inflammatory infiltrate and a reduced extent of fibrosis were observed in the PVE group only.

CONCLUSIONS

Use of 18F-FDG-PET/CT at the initial presentation of patients with suspected PVE increases the diagnostic capability of the modified Duke criteria. In patients who present with suspected NVE, the use of 18F-FDG-PET/CT is less accurate and could only be considered a complementary diagnostic tool for a specific population of patients with NVE.

Symptoms, left ventricular function, and timing of valve replacement surgery in patients with aortic regurgitation

BACKGROUND

Because cardiac decompensation is subtle, the best time to perform aortic valve replacement surgery may be difficult to determine. We investigated the relation of symptoms to left ventricular (LV) function and the timing of valve replacement in patients with aortic regurgitation (AR) of largely rheumatic origin.

METHODS

Sixty-eight initially asymptomatic patients (mean age 29 years) with severe chronic AR were monitored for 36 months. Assessments included baseline and yearly echocardiograms and radioisotope ventriculography (resting and exercise) and clinical examinations every 6 months.

RESULTS

Forty-seven patients (69%) remained asymptomatic and 21 (31%) had symptoms develop after 24 to 36 months. Compared with symptomatic patients, asymptomatic patients had significantly (P <.05) lower baseline LV end-diastolic diameter, end-systolic diameter, end-systolic stress, and volume/mass ratio but greater shortening fraction and ejection fraction (EF) at rest. These variables remained stable without statistically significant change until surgical correction in symptomatic patients. Percent variation of EF from rest to exercise increased in patients who remained asymptomatic (EF 2.8% +/- 10.6%) but decreased in those who became symptomatic (EF -4.2% +/- 13%; P <.05). Twenty symptomatic patients (New York Heart Association class III/IV, angina and/or syncope) had valve replacement surgery, after which all were in New York Heart Association class I/II and had significant decreases of LV end-diastolic and end-systolic diameters and an increase on percent variation of EF from rest to exercise (P <.0001).

CONCLUSIONS

Development of symptoms did not correlate with change in any ventricular function indexes. Surgery on appearance of symptoms restored LV function to near normal.

Biomarkers for prediction of mortality in left-sided infective endocarditis

BACKGROUND

Evidence regarding biomarkers for risk prediction in patients with infective endocarditis (IE) is limited. We aimed to investigate the value of a panel of biomarkers for the prediction of in-hospital mortality in patients with IE.

METHODS

Between 2016 and 2018, consecutive IE patients admitted to the emergency department were prospectively included. Blood concentrations of nine biomarkers were measured at admission (D0) and on the seventh day (D7) of antibiotic therapy: C-reactive protein (CRP), sensitive troponin I (s-cTnI), procalcitonin, B-type natriuretic peptide (BNP), neutrophil gelatinase-associated lipocalin (NGAL), interleukin 6 (IL6), tumor necrosis factor α (TNF-α), proadrenomedullin, alpha-1-acid glycoprotein, and galectin 3. The primary endpoint was in-hospital mortality.

RESULTS

Among 97 patients, 56% underwent cardiac surgery, and in-hospital mortality was 27%. At admission, six biomarkers were independent predictors of in-hospital mortality: s-cTnI (OR 3.4; 95%CI 1.8-6.4; P<0.001), BNP (OR 2.7; 95%CI 1.4-5.1; P=0.002), IL-6 (OR 2.06; 95%CI 1.3-3.7; P=0.019), procalcitonin (OR 1.9; 95%CI 1.1-3.2; P=0.018), TNF-α (OR 1.8; 95%CI 1.1-2.9; P=0.019), and CRP (OR 1.8; 95%CI 1.0-3.3; P=0.037). At admission, S-cTnI provided the highest accuracy for predicting mortality (area under the ROC curve: s-cTnI 0.812, BNP 0.727, IL-6 0.734, procalcitonin 0.684, TNF-α 0.675, CRP 0.670). After 7 days of antibiotic therapy, BNP and inflammatory biomarkers improved their performance (s-cTnI 0.814, BNP 0.823, IL-6 0.695, procalcitonin 0.802, TNF-α 0.554, CRP 0.759).

CONCLUSION

S-cTnI concentration measured at admission had the highest accuracy for mortality prediction in patients with IE.

Impact of Acute Kidney Injury on Short- and Long-term Outcomes After Transcatheter Aortic Valve Implantation

INTRODUCTION AND OBJECTIVES

Acute kidney injury (AKI) is frequently observed after transcatheter aortic valve implantation (TAVI) and is associated with higher mortality. However, the impact of AKI on long-term outcomes remains controversial. Therefore, we sought to evaluate the impact of AKI on short- and long-term outcomes following TAVI using the Valve Academic Research Consortium 2 criteria.

METHODS

Consecutive patients (n = 794) with severe aortic stenosis who underwent TAVI were included in a multicenter Brazilian registry. Logistic regression analysis was used to identify predictors of AKI. Four-year outcomes were determined as Kaplan-Meier survival curves, and an adjusted landmark analysis was used to test the impact of AKI on mortality among survivors at 12 months.

RESULTS

The incidence of AKI after TAVI was 18%. Independent predictors of AKI were age, diabetes mellitus, major or life-threatening bleeding and valve malpositioning. Acute kidney injury was independently associated with higher risk of all-cause death (adjusted HR, 2.8; 95%CI, 2.0-3.9; P < .001) and cardiovascular mortality (adjusted HR, 2.9; 95%CI, 1.9-4.4; P < .001) over the entire follow-up period. However, when considering only survivors at 12 months, there was no difference in both clinical endpoints (adjusted HR, 1.2; 95%CI, 0.5-2.4; P = .71, and HR, 0.7; 95%CI, 0.2-2.1; P = .57, respectively).

CONCLUSIONS

Acute kidney injury is a frequent complication after TAVI. Older age, diabetes, major or life-threatening bleeding, and valve malpositioning were independent predictors of AKI. Acute kidney injury is associated with worse short- and long-term outcomes. However, the major impact of AKI on mortality is limited to the first year after TAVI.

Non-toxigenic Corynebacterium diphtheriae infective endocarditis with embolic events: a case report

Background

Corynebacterium diphtheriae (C. diphtheriae) infections, usually related to upper airways involvement, could be highly invasive. Especially in developing countries, non-toxigenic C. diphtheriae strains are now emerging as cause of invasive disease like endocarditis. The present case stands out for reinforcing the high virulence of this pathogen, demonstrated by the multiple systemic embolism and severe valve deterioration. It also emphasizes the importance of a coordinated interdisciplinary work to address all these challenges related to infectious endocarditis.

Case presentation

A 21-year-old male cocaine drug abuser presented to the emergency department with a 1-week history of fever, asthenia and dyspnea. His physical examination revealed a mitral systolic murmur, signs of acute arterial occlusion of the left lower limb, severe arterial hypotension and acute respiratory failure, with need of vasoactive drugs, orotracheal intubation/mechanical ventilation, empiric antimicrobial therapy and emergent endovascular treatment. The clinical suspicion of acute infective endocarditis was confirmed by transesophageal echocardiography, demonstrating a large vegetation on the mitral valve associated with severe valvular regurgitation. Abdominal ultrasound was normal with no hepatic, renal, or spleen abscess. Serial blood cultures and thrombus culture, obtained in the vascular procedure, identified non-toxigenic C. diphtheriae, with antibiotic therapy adjustment to monotherapy with ampicillin. Since the patient had a severe septic shock with sustained fever, despite antimicrobial therapy, urgent cardiac surgical intervention was planned. Anatomical findings were compatible with an aggressive endocarditis, requiring mitral valve replacement for a biological prosthesis. During the postoperative period, despite an initial clinical recovery and successfully weaning from mechanical ventilation, the patient presented with a recrudescent daily fever. Computed tomography of the abdomen revealed a hypoattenuating and extensive splenic lesion suggestive of abscess. After sonographically guided bridging percutaneous catheter drainage, surgical splenectomy was performed. Despite left limb revascularization, a forefoot amputation was required due to gangrene. The patient had a good clinical recovery, fulfilling 4-weeks of antimicrobial treatment.

Conclusion

Despite the effectiveness of toxoid-based vaccines, recent global outbreaks of invasive C. diphtheriae infectious related to non-toxigenic strains have been described. These infectious could be highly invasive as demonstrated in this case. Interdisciplinary work with an institutional “endocarditis team” is essential to achieve favorable clinical outcomes in such defiant scenarios.

Potential of transcatheter aortic valve replacement to improve post-procedure renal function

BACKGROUND

Baseline comorbidities including renal dysfunction are frequently found in patients treated with transcatheter aortic valve replacement (TAVR) and may increase the risks of acute kidney injury (AKI), although some of them may actually improve renal function. We aimed to evaluate the potential of TAVR to acutely improve post-procedure renal function.

METHODS

This is a prospective single-center registry of consecutive patients with severe symptomatic aortic stenosis treated by transfemoral TAVR. Creatinine levels were determined at baseline and daily until hospital discharge. AKI was defined according to VARC-2 criteria. Patients who had improvement of creatinine levels >25% were classified as having TAVR induced renal function improvement (TIRFI).

RESULTS

A total of 69 patients undergoing TAVR were included, with a mean age of 83.0±7.4 years, being 24.6% diabetics, with a median STS score of 9.2 (5.1-21.6). Using the VARC-2 criteria, the majority of patients (64.6%) did not have renal impairment, while AKI was detected in 35.4% of the patients. Importantly, in those with prior severe renal dysfunction (clearance <30mL/min/1.73m²) or diabetes, AKI reached up to 50% and 56.3% of the patients, respectively. Conversely, acute kidney recovery (TIRFI) occurred in 12 patients (18.5%) being >50% in 1 patient (1.5%), and at hospital discharge the majority of the patients (88.6%) left the hospital in their original or better renal function categories.

CONCLUSION

Despite multiple comorbidities in a selected TAVR-population and the use of contrast media, TAVR did not impair renal function in a majority of patients, with a significant proportion of them rather having acute renal function improvement.

Arterial distensibility as a possible compensatory mechanism in chronic aortic insufficiency

OBJECTIVE

To evaluate elastic properties of conduit arteries in asymptomatic patients who have severe chronic aortic regurgitation.

METHODS

Twelve healthy volunteers aged 30+/-1 years (control group) and 14 asymptomatic patients with severe aortic regurgitation aged 29+/-2 years and left ventricular ejection fraction of 0.61+/-0.02 (radioisotope ventriculography) were studied. High-resolution ultrasonography was performed to measure the systolic and diastolic diameters of the common carotid artery. Simultaneous measurement of blood pressure enabled the calculation of arterial compliance and distensibility.

RESULTS

No differences were observed between patients with aortic regurgitation and the control group concerning age, sex, body surface, and mean blood pressure. Pulse pressure was significantly higher in the aortic regurgitation group compared with that in the control group (78+/-3 versus 48+/-1mmHg, P<0.01). Arterial compliance and distensibility were significantly greater in the aortic regurgitation group compared with that in the control group (11.0+/-0.8 versus 8.1+/-0.7 10(-10) N-1 m4, P=0.01 e and 39.3+/-2.6 versus 31.1+/-2.0 10(-6) N-1 m2, P=0.02, respectively).

CONCLUSION

Patients with chronic aortic regurgitation have increased arterial distensibility. Greater vascular compliance, to lessen the impact of systolic volume ejected into conduit arteries, represents a compensatory mechanism in left ventricular and arterial system coupling.