Do clinical diagnoses correlate with pathological diagnoses in cardiac transplant patients? The importance of endomyocardial biopsy

Cardiac Sarcoidosis: A Comprehensive Clinical Review

Sarcoidosis is an inflammatory multisystemic disease of unknown etiology characterized by the formation of non-caseating granulomas. Sarcoidosis can affect any organ, predominantly the lungs, lymphatic system, skin and eyes. While > 90% of patients with sarcoidosis have lung involvement, an estimated 5% of patients with sarcoidosis have clinically manifest cardiac sarcoidosis (CS), whereas approximately 25% have asymptomatic, clinically silent cardiac involvement verified by autopsy or imaging studies. CS can present with conduction disturbances, ventricular arrhythmias, heart failure or sudden cardiac death. Approximately 30% of < 60-year-old patients presenting with unexplained high degree atrioventricular (AV) block or ventricular tachycardia are diagnosed with CS, therefore CS should be strongly considered in such patients. CS is the second leading cause of death among patients affected by sarcoidosis after pulmonary sarcoidosis, therefore its early recognition is important, because early treatment may prevent death from cardiovascular involvement. The establishment of isolated CS diagnosis sometimes can be quite difficult, when extracardiac disease cannot be verified. The other reason for the difficulty to diagnose CS is that CS is a chameleon of cardiology and it can mimic (completely or almost completely) different cardiac diseases, such as arrhythmogenic cardiomyopathy, giant cell myocarditis, dilated, restrictive and hypertrophic cardiomyopathies. In this review article we will discuss the current diagnosis and management of CS and delineate the potential difficulties and pitfalls of establishing the diagnosis in atypical cases of isolated CS.

Pursuit of "endpoint diagnoses" as a cognitive forcing strategy to avoid premature diagnostic closure

Premature closure is often described as a significant contributor to diagnostic error. Therefore, developing strategies to mitigate premature closure could reduce diagnostic errors and improve patient care. Here we propose the novel concept of pursuit of an "endpoint diagnosis" as a cognitive forcing strategy (CFS) for avoiding premature diagnostic closure. We define an "endpoint diagnosis" as an underlying causative explanation for a patient's signs, symptoms, and laboratory and radiographic data that exhausts additional relevant diagnostic evaluation. We have observed four contexts in which the error of not pursuing an endpoint diagnosis most often occurs: (1) diagnoses that appear to result in the same treatment regardless of etiology, (2) cases that are particularly complex, (3) clinical scenarios that are vulnerable to systems errors, and (4) situations in which patients' problems are attributed to uncontrolled underlying risk factors or an exacerbation of a known condition. Additionally, we address why we believe endpoint diagnoses are not universally pursued, delineate when this approach might be particularly useful, attempt to reconcile the potential conflict between accepting diagnostic ambiguity in certain instances and pursuing endpoint diagnoses, and outline possible concerns that might arise with using this CFS, including the possibility of lengthy evaluations resulting in overdiagnosis and overtreatment. Our overarching goal is for this CFS to help clinicians in their daily clinical practice as they seek to optimize their diagnostic skill and patient care.

The discrepancies between clinical and histopathological diagnoses of cardiomyopathies in patients with stage D heart failure undergoing heart transplantation

Background

This study aimed to determine the etiology of stage-D heart failure (HF) and the prevalence and prognosis of misdiagnosed cardiomyopathy in patients undergoing heart transplantation.

Methods and results

We retrospectively reviewed 127 consecutive patients (mean age, 42 years; 90 [71%], male) from February 1994 to September 2021 admitted for heart transplant in our tertiary center. Pre-transplant clinical diagnosis was compared with post-transplant pathological diagnosis. The most common misdiagnosed cardiomyopathy was nonischemic cardiomyopathy accounting for 6% (n = 8) of all patients. Histopathological examination of explanted hearts in misdiagnosed patients revealed 2 arrhythmogenic cardiomyopathy, 2 sarcoidosis, 1 hypertrophic cardiomyopathy, 1 hypersensitivity myocarditis, 1 noncompacted cardiomyopathy, and 1 ischemic cardiomyopathy. Pre-transplant cardiac MRI and endomyocardial biopsy (EMB) were performed in 33 (26%) and 6 (5%) patients, respectively, with both performed in 3 (3% of patients). None of the patients undergoing both cardiac tests were misdiagnosed. During the 5-years follow-up period, 2 (25%) and 44 (37%) patients with and without pretransplant misdiagnosed cardiomyopathy died. There was no difference in survival rate between the groups (hazard ratio: 0.52; 95% CI:0.11–2.93; P = 0.314).

Conclusions

The prevalence of misdiagnosed cardiomyopathy was 6% of patients with stage-D HF undergoing heart transplantation, the misdiagnosis mostly occurred in nonischemic/dilated cardiomyopathy. An accurate diagnosis of newly detected cardiomyopathy gives an opportunity for potentially reversing cardiomyopathy, including sarcoidosis or myocarditis. This strategy may minimize the need for advanced HF therapy or heart transplantation. With advances in cardiac imaging, improvements in diagnostic accuracy of the etiology of HF can improve targeting of treatment.

Missed Opportunities in Identifying Cardiomyopathy Aetiology Prior to Advanced Heart Failure Therapy

BACKGROUND

Specific aetiologies of cardiomyopathy can significantly impact treatment options as well as appropriateness and prioritisation for advanced heart failure therapies such as ventricular assist device (VAD) or orthotopic heart transplantation (OHT). We reviewed the tissue diagnoses of patients who underwent advanced therapies for heart failure (HF) to identify diagnostic discrepancies.

METHODS

This study presents a retrospective cohort of the aetiology of cardiomyopathy in 118 patients receiving either durable VAD or OHT. Discrepancies between the preoperative aetiological diagnosis of cardiomyopathy with the pathological diagnosis were recorded. Echocardiographic and haemodynamic data were reviewed to examine differences in patients with differing aetiological diagnoses.

RESULTS

Twelve (12) of 118 (12/118) (10.2%) had a pathological diagnosis that was discordant with pre-surgical diagnosis. The most common missed diagnoses were infiltrative cardiomyopathy (5) and hypertrophic cardiomyopathy (3). Patients with misidentified aetiology of cardiomyopathy had smaller left ventricular (LV) dimensions on echocardiography than patients with dilated cardiomyopathy (5.8±0.9 vs 6.7±1.1 respectively p=0.01).

CONCLUSIONS

Most HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, but a missed diagnosis at time of intervention (VAD or OHT) was not uncommon. Smaller LV dimension on echocardiogram in a patient with a non-ischaemic cardiomyopathy warrants further workup for a more specific aetiology.

Frequency of Congruence and Incongruence Between the Clinical and Morphological Diagnoses in Patients Having Orthotopic Heart Transplantations at the Baylor University Medical Center at Dallas From 1993 to 2020

We studied the explanted hearts of 519 patients having Orthotopic Heart Transplant (OHT) at Baylor University Medical Center from 2013 to 2020 and compared the morphologic diagnoses to the clinical diagnoses before OHT. We then combined these findings with the findings from 314 patients who had been studied in the laboratory from 1993 to 2012. Thus, the total number of patients included in the overall study were 833. Among the 833 patients the morphologic and clinical diagnoses were congruent in 760 (91%) and incongruent in 73 (9%) cases. Most of the incongruity occurred among the patients with cardiac sarcoidosis (27/36 [75%]), arrhythmogenic right ventricular cardiomyopathy (11/19 [58%]), and hypertrophic cardiomyopathy (8/25 [32%]). The frequency of incongruence among 833 patients having OHT in an 27 year period was 9%, with no significant difference between the 314 patients studied from 1998 to 2012, and the 519 studied from 2013 to 2020.

Evaluation of cardiomyopathy diagnosis in heart transplant recipients: comparison of echocardiographic and pathologic classification

Background

Definite diagnosis of cardiomyopathy types can be challenging in end-stage disease process. New growing data have suggested that there is inconsistency between echocardiography and pathology in defining type of cardiomyopathy before and after heart transplantation. The aim of the present study was to compare the pre-heart transplant echocardiographic diagnosis of cardiomyopathy with the results of post-transplant pathologic diagnosis.

Results

In this retrospective cross-sectional clinicopathological study, 100 consecutive patients have undergone heart transplantation in Masih-Daneshvari hospital, Tehran, Iran, between 2010 and 2019. The mean age of patients was 40 ± 13 years and 79% of patients were male. The frequency of different types of cardiomyopathy was significantly different between two diagnostic tools (echocardiography versus pathology, P < 0.001). On the other hand, in 24 patients, the results of echocardiography as regard to the type of cardiomyopathy were inconsistent with pathologic findings.

Conclusion

Based on the findings of the present study, it could be concluded that there is a significant difference between echocardiographic and pathologic diagnosis of cardiomyopathy; therefore, it is necessary to use additional tools for definite diagnosis of cardiomyopathy like advanced cardiac imaging or even endomyocardial biopsy before heart transplantation to reach an appropriate treatment strategy.

The Human Explanted Heart Program: A translational bridge for cardiovascular medicine

The progression of cardiovascular research is often impeded by the lack of reliable disease models that fully recapitulate the pathogenesis in humans. These limitations apply to both in vitro models such as cell-based cultures and in vivo animal models which invariably are limited to simulate the complexity of cardiovascular disease in humans. Implementing human heart tissue in cardiovascular research complements our research strategy using preclinical models. We established the Human Explanted Heart Program (HELP) which integrates clinical, tissue and molecular phenotyping thereby providing a comprehensive evaluation into human heart disease. Our collection and storage of biospecimens allow them to retain key pathogenic findings while providing novel insights into human heart failure. The use of human non-failing control explanted hearts provides a valuable comparison group for the diseased explanted hearts. Using HELP we have been able to create a tissue repository which have been used for genetic, molecular, cellular, and histological studies. This review describes the process of collection and use of explanted human heart specimens encompassing a spectrum of pediatric and adult heart diseases, while highlighting the role of these invaluable specimens in translational research. Furthermore, we highlight the efficient procurement and bio-preservation approaches ensuring analytical quality of heart specimens acquired in the context of heart donation and transplantation.

Myocardial Involvement in Patients With Histologically Diagnosed Cardiac Sarcoidosis: A Systematic Review and Meta-Analysis of Gross Pathological Images From Autopsy or Cardiac Transplantation Cases

Background In patients with suspected cardiac sarcoidosis, late gadolinium enhancement on cardiovascular magnetic resonance imaging and/or 18F-fluorodeoxyglucose uptake on positron emission tomography are often used to reach a clinical diagnosis of cardiac sarcoidosis. On the basis of data from the imaging literature of clinical cardiac sarcoidosis, no specific features of myocardial involvement are regarded as pathognomonic for cardiac sarcoidosis. Thus, a diagnosis of cardiac sarcoidosis is challenging to make. There has been no systematic analysis of histologically diagnosed cardiac sarcoidosis for patterns of myocardial involvement. We hypothesized that certain patterns of myocardial involvement are more frequent in histologically diagnosed cardiac sarcoidosis. Methods and Results We performed a systematic review and meta-analysis of gross pathological images from the published literature of patients with histologically diagnosed cardiac sarcoidosis who underwent autopsy or cardiac transplantation. Thirty-three eligible articles provided images of 49 unique hearts. Analysis of these hearts revealed certain features of myocardial involvement in >90% of cases: left ventricular (LV) subepicardial, LV multifocal, septal, and right ventricular free wall involvement. In contrast, other patterns were seen in 0% to 6% of cases: absence of gross LV myocardial involvement, isolated LV midmyocardial involvement, isolated LV subendocardial involvement, isolated LV transmural involvement, absence of septal involvement, or isolated involvement of only one LV level. Conclusions In this systematic review and meta-analysis of histologically diagnosed cardiac sarcoidosis, we identified certain features of myocardial involvement that occurred frequently and others that occurred rarely or never. These patterns could aid the interpretation of cardiovascular magnetic resonance imaging and positron emission tomography imaging and improve the diagnosis and the prognostication of patients with suspected cardiac sarcoidosis.

Impact of Cardiovascular Magnetic Resonance Imaging on Identifying the Etiology of Cardiomyopathy in Patients Undergoing Cardiac Transplantation

Errors in identifying the etiology of cardiomyopathy have been described in patients undergoing cardiac transplantation. There are increasing data that cardiovascular magnetic resonance imaging (CMR) provides unique diagnostic information in heart failure. We investigated the association of the performance of CMR prior to cardiac transplantation with rates of errors in identifying the etiology of cardiomyopathy. We compared pre-transplantation clinical diagnoses with post-transplantation pathology diagnoses obtained from the explanted native hearts. Among 338 patients, there were 23 (7%) errors in identifying the etiology of cardiomyopathy. Of these, 22 (96%) occurred in patients with pre-transplantation clinical diagnoses of non-ischemic cardiomyopathy (NICM). Only 61/338 (18%) had CMRs prior to transplantation. There was no significant association between the performance of CMR and errors in the entire study cohort (p = 0.093). Among patients with pre-transplantation clinical diagnoses of NICM, there was a significant inverse association between the performance of CMR and errors (2.4% vs. 14.6% in patients with and without CMR respectively; p = 0.030). In conclusion, CMR was underutilized prior to cardiac transplantation. In patients with pre-transplantation clinical diagnoses of NICM - in whom 96% of errors in identifying the etiology of cardiomyopathy occurred - the performance of CMR was associated with significantly fewer errors.

Verification of Heart Disease: Implications for a New Heart Transplantation Allocation System

OBJECTIVES

This study sought to determine the accuracy of the pre-transplantation clinical diagnosis of heart disease in the United Network for Organ Sharing (UNOS) database.

BACKGROUND

Because survival on the heart transplantation waitlist depends on underlying heart disease, a new allocation system will include the type of heart disease. Accuracy of the pre-transplantation clinical diagnosis and the effect of misclassification are unknown.

METHODS

We included all adults who received transplants at our center between January 2009 to December 2015. We compared the pre-transplantation clinical diagnosis at listing with pathology of the explanted heart and determined the potential effect of misclassification with the proposed allocation system.

RESULTS

A total of 334 patients had the following clinical cardiac diagnoses at listing: 148 had dilated cardiomyopathy, 19 had restrictive cardiomyopathy, 103 had ischemic cardiomyopathy, 24 had hypertrophic cardiomyopathy, 11 had valvular disease, 16 had congenital heart disease (CHD), and 13 patients had a diagnosis of "other." Pathology of the explanted hearts revealed 82% concordance and 18% discordance (10% coding errors and 8% incorrect diagnosis). The most common incorrect diagnoses were sarcoidosis (66%), arrhythmogenic right ventricular dysplasia (60%), and other causes of predominately right-sided heart failure (33%). Among the misclassified diagnoses, 40% were listed as UNOS status 2, 8% remained at status 2 at transplantation, and only sarcoidosis and CHD were potentially at a disadvantage with the new allocation.

CONCLUSIONS

There is high concordance between clinical and pathologic diagnosis, except for sarcoidosis and genetic diseases. Few misclassifications result in disadvantages to patients based on the new allocation system, but rare diseases like sarcoidosis remain problematic. To improve the UNOS database and enhance outcome research, pathology of the explanted hearts should be required post-transplantation.

Fulminant heart failure due to giant cell myocarditis affecting the left ventricle

A 56-year-old woman, previously healthy, was hospitalized after an episode of ventricular tachycardia in the course of infection. In view of the fulminant course of heart failure the patient was connected to an extracorporeal membrane oxygenation (ECMO) system. After 3 weeks of treatment with ECMO the patient received a heart transplant. A histopathological examination of the tissues of the explanted heart revealed giant cell myocarditis. The patient was treated with immunosuppression based on induction therapy followed by a standard regimen with steroids. Currently, the patient remains in good general condition with an left ventricular ejection fraction of 60%.

Morphologic features of the recipient heart in patients having cardiac transplantation and analysis of the congruence or incongruence between the clinical and morphologic diagnoses

Cardiac transplantation (CT) has been one of the great medical advances of the last nearly 50 years. We studied the explanted hearts of 314 patients having CT at Baylor University Medical Center Dallas from 1993 to 2012, and compared the morphologic diagnoses to the clinical diagnoses before CT. Among the 314 patients the morphologic and clinical diagnoses were congruent in 272 (87%) and incongruent in 42 (13%). Most of the incongruity occurred among the 166 patients with non-ischemic cardiomyopathy (non-IC) (36/166 [22%]), and of that group the major incongruity occurred among the patients with hypertrophic cardiomyopathy (7/17 [41%]), non-compaction left ventricular cardiomyopathy (NCLVC) (3/3 [100%]), mononuclear myocarditis (3/3 [100%]), arrhythmogenic right ventricular cardiomyopathy (ARVC) (4/4 [100%]), and cardiac sarcoidosis (8/8 [100%]). The phrase "non-IC" is a general term that includes several subsets of cardiac diseases and simply means "insignificant narrowing of 1 or more of the epicardial coronary arteries," but it does not specify the specific cause of the heart failure leading to CT. A number of cardiac illustrations are provided to demonstrate the morphologic variability occurring among the patients with IC and non-IC.

Right ventricular sarcoidosis: is it time for updated diagnostic criteria?

A 55-year-old woman with a history of complete heart block, atrial flutter, and progressive right ventricular failure was referred to our tertiary care center to be evaluated for cardiac transplantation. The patient's clinical course included worsening right ventricular dysfunction for 3 years before the current evaluation. Our clinical findings raised concerns about arrhythmogenic right ventricular cardiomyopathy. Noninvasive imaging, including a positron emission tomographic scan, did not reveal obvious myocardial pathologic conditions. Given the end-stage nature of the patient's right ventricular failure and her dependence on inotropic agents, she underwent urgent listing and subsequent heart transplantation. Pathologic examination of the explanted heart revealed isolated right ventricular sarcoidosis with replacement fibrosis. Biopsy samples of the cardiac allograft 6 months after transplantation showed no recurrence of sarcoidosis. This atypical presentation of isolated cardiac sarcoidosis posed a considerable diagnostic challenge. In addition to discussing the patient's case, we review the relevant medical literature and discuss the need for updated differential diagnostic criteria for end-stage right ventricular failure that mimics arrhythmogenic right ventricular cardiomyopathy.

Morphologic features of cardiac sarcoidosis in native hearts of patients having cardiac transplantation

Described herein are 10 patients who underwent cardiac transplantation (CT) for severe chronic systolic heart failure resulting from cardiac sarcoidosis. None had the diagnosis of sarcoidosis established before CT except for the 3 patients who earlier had had a portion of left ventricular wall excised for insertion of a left ventricular assist device and non-caseating granulomas were present in the removed myocardium. Although none of the 10 patients had significant narrowing of any of the epicardial coronary arteries, all had focal scarring of the walls of the left and right ventricles and ventricular septum and all had dilated ventricular cavities. The patients with the most ventricular wall scarring tended to have the fewest sarcoid granulomas in the ventricular walls. Two patients had no sarcoid granulomas in the excised heart although one did have typical sarcoid granulomas in the portion of left ventricular wall excised to insert a left ventricular assist device. Patients with cardiac sarcoidosis severe enough to warrant CT had characteristic cardiac ventricular morphologic findings, and no dysfunction of other non-cardiac organs, making clinical diagnosis of cardiac sarcoidosis rather difficult.

Capability of three-dimensional speckle tracking radial strain for identification of patients with cardiac sarcoidosis

Since cardiac sarcoidosis (CS) leads to substantial morbidity and sudden death, early diagnosis and appropriate management are crucial for patients with CS. Echocardiography used to be considered a useful diagnostic tool for patients with CS, but CS may clinically present as dilated cardiomyopathy (DCM). Our objective was to investigate whether a novel three-dimensional (3-D) speckle-tracking strain can identify patients with CS more accurately. We studied 23 CS patients with an ejection fraction (EF) of 46 ± 10 %, and 16 EF-matched patients with DCM (EF 45 ± 11 %). Global radial (GRS), circumferential (GCS) and longitudinal (GLS) strain was assessed using 3-D speckle-tracking system. GRS of patients with CS was significantly lower than that of patients with DCM (18.5 ± 8.4 vs. 28.5 ± 8.3 %, p < 0.01), but GCS and GLS in patients with CS and DCM were similar. GRS ≦ 21.1 could differentiate CS from DCM with a sensitivity of 70 %, specificity of 88 % and area under the curve of 0.79. An additional noteworthy findings was that, patients with CS showed more negative radial strain curves than did those with DCM (1.7 ± 2.3 vs. 0.1 ± 0.5, p < 0.01). In conclusion, 3-D speckle-tracking radial strain shows good potential to distinguish CS from DCM. Our observations can thus be expected to have clinical implications for management of CS patients.

Cardiac amyloidosis: what are the indications for transplant?

PURPOSE OF REVIEW

We review the clinical and pathological features of the various types of amyloid that involve the heart, the diagnostic utility of endomyocardial biopsy, and the experience of patient survival and disease recurrence following cardiac transplant for amyloidosis.

RECENT FINDINGS

Patient outcome is dependent on arresting the cause of amyloid as well as controlling the accumulated damage, which may involve multiple organs. As such, the stratification of patient suitability for cardiac transplant must be considered in conjunction with concurrent treatments, which may include autologous stem cell, liver or kidney transplant, and chemotherapy.

SUMMARY

As the efficacy of these therapies changes, the indications for cardiac transplantation need to be re-evaluated.

2011 consensus statement on endomyocardial biopsy from the Association for European Cardiovascular Pathology and the Society for Cardiovascular Pathology

The Association for European Cardiovascular Pathology and the Society for Cardiovascular Pathology have produced this position paper concerning the current role of endomyocardial biopsy (EMB) for the diagnosis of cardiac diseases and its contribution to patient management, focusing on pathological issues, with these aims: • Determining appropriate EMB use in the context of current diagnostic strategies for cardiac diseases and providing recommendations for its rational utilization • Providing standard criteria and guidance for appropriate tissue triage and pathological analysis • Promoting a team approach to EMB use, integrating the competences of pathologists, clinicians, and imagers.

Differences in antiapoptotic, proliferative activities and morphometry in dilated and ischemic cardiomyopathy: study of hearts explanted from transplant recipients

BACKGROUND

Antiapoptotic as well as replacement and proliferative mechanisms take place in the myocardium in dilated cardiomyopathy (DCM) and ischemic heart disease (IHD). We sought to estimate antiapoptotic, proliferative and replacement activities in cardiomyopathies.

MATERIALS

The study groups included seven hearts with DCM and eight with IHD, which had been explanted at the time of transplantation. The comparator group consisted of cases of myocardial hypertrophy and the control group, donor fragments.

METHODS

Antiapoptotic and proliferative responses were determined immunohistochemically as Bcl-2 and Ki67 expression by semiquantitative assessment of the intensity of staining. We also measured and statistically analyzed the integrative morphometric measurements of the fraction of fibrosis area, the nucleosarcoplasmic ratio, and cardiocyte diameter.

RESULTS

No Bcl-2 expression was observed in the controls. The strongest reaction was seen in the DCM group, then in the IHD, and in the comparator group of myocardial hypertrophy. Proliferative activity was seen only in endocardial and interstitial fibroblasts in DCM and IHD cases. The cardiocyte diameter showed no statistical association between myocardial hypertrophy and IHD, or IHD and DCM, whereas the nucleosarcoplasmic ratios were significantly different from control groups for all comparisons. Myocardial fibrosis showed the highest values in DCM and IHD. Discriminant analysis showed the value of interstitial fibrosis and cardiocyte diameter to categorize the analyzed groups.

CONCLUSIONS

Antiapoptotic Bcl-2 activity seemed to play an important role in cardiocyte preservation, while proliferative activity was resticted to interstitial connective tissue cells as a replacement process. Myocardial Bcl-2 expression, the extent of myocardial fibrosis, and cardiocyte diameter may serve as additional diagnostic tools to differentiate cardiomyopathies.