Nonobstructive epicardial coronary artery disease: an evolving concept in need of diagnostic and therapeutic guidance.

For decades, we have been treating patients presenting with angina and concerning electrocardiographic changes indicative of ischemia or injury, in whom no culprit epicardial coronary stenosis was found during diagnostic coronary angiography. Unfortunately, the clinical outcomes of these patients were not better than those with recognized obstructive coronary disease. Improvements in technology have allowed us to better characterize these patients. Consequently, an increasing number of patients with ischemia and no obstructive coronary artery disease (INOCA) or myocardial infarction in the absence of coronary artery disease (MINOCA) have now gained formal recognition and are more commonly encountered in clinical practice. Although both entities might share functional similarities at their core, they pose significant diagnostic and therapeutic challenges. Unless we become more proficient in identifying these patients, particularly those at higher risk, morbidity and mortality outcomes will not improve. Though this field remains in constant flux, data continue to become available. Therefore, we thought it would be useful to highlight important milestones that have been recognized so we can all learn about these clinical entities. Despite all the progress made regarding INOCA and MINOCA, many important knowledge gaps continue to exist. For the time being, prompt identification and early diagnosis remain crucial in managing these patients. Even though we are still not clear whether intensive medical therapy alters clinical outcomes, we remain vigilant and wait for more data.

Challenges of Management of Subaortic Membrane in a Young Adult Patient: A Case Report.

This article presents a case review and literature review focused on the challenges of managing subaortic membranes (SAMs) in young adult patients with mild aortic regurgitation (AR) or aortic stenosis (AS). The study aims to discuss the diagnosis of SAM, the imaging studies used for assessment, the management strategies in young patients, the risk of valvular damage, and the controversy surrounding prophylactic resection in mild AR. The management of SAM in adults poses challenges due to limited treatment options and potential complications, necessitating further investigation into the progression of AS and AR in asymptomatic SAM patients. The case presentation describes a 40-year-old male with muscular dystrophy who presented with symptoms and was diagnosed with SAM. Various imaging techniques, including CT chest, transthoracic echocardiogram (TTE), and transesophageal echocardiogram (TEE), were used to confirm the presence and severity of SAM. Based on the patient's clinical profile and the absence of surgical indications, medical therapy was initiated, and regular outpatient follow-up was recommended to monitor disease progression. The discussion highlights the challenges in diagnosing SAM, the importance of imaging studies, and the potential complications associated with SAM in young patients. The article also explores the management options for SAM, emphasizing surgical resection as the definitive treatment, while acknowledging the limited success rates of alternative approaches. Close monitoring and prompt intervention for complications are crucial in the management of SAM. The concluding statement emphasizes the need for further research to explore alternative treatments for SAM in young patients.

CT-Guided Pericardiocentesis in a Case of Tension Pneumopericardium and Tamponade Secondary to an Enteropericardial Fistula.

Tension pneumopericardium is most commonly traumatic. Nontraumatic etiologies are rare, but have been reported with gastropericardial and esophagopericardial fistulas. We present the case of a 54-year-old patient who developed a tension pneumopericardium with tamponade secondary to a perforated marginal ulcer in the proximal jejunum with an enteropericardial fistula. (Level of Difficulty: Intermediate.).

Heart Failure with Preserved Left Ventricular Ejection Fraction: A Complex Conundrum Simply Not Limited to Diastolic Dysfunction.

Over the last two decades, the changing paradigm of heart failure with preserved ejection fraction (HFpEF) has transformed our understanding not only of the pathophysiology of this clinical entity but also the diagnostic and therapeutic approaches aimed at treating this complex patient population. No longer HFpEF should be seen as simply left ventricular diastolic dysfunction but as a group of that in addition of having small and thick left ventricles with abnormal diastolic filling patterns as their main pathophysiologic abnormality; they also have whole host of different abnormalities. In fact, this heterogeneous clinical entity embodies numerous mechanisms and is linked to multiorgan dysfunction, with hypertension and obesity playing a major role. Although we have gained an enormous amount of understanding not only on the causes but also the downstream effects of HFpEF, there is still much to be learned before we can fully comprehend this complex clinical entity. It is the main intention of this review to synthesize the most recent attributes, mechanism, diagnostic tools, and most useful therapeutic alternatives to be considered when evaluating patients either complaining of dyspnea on exertion as well as exercise intolerance or those recently admitted with HF symptoms but with normal LVEF in the absence of any other valvular abnormalities.

Gastrointestinal bleeding in recipients of left ventricular assist devices-a systematic review.

The twenty-first century has revolutionized the management of congestive heart failure with the widespread use of left ventricular assist devices and other treatment modalities that improve morbidity and mortality after the failure of medical management. These novel devices come with significant side effects. One of the most common side effects of left ventricular assist devices is the increased frequency of lower gastrointestinal bleeding compared to heart failure patients without left ventricular assist devices. Multiple etiologies of recurrent gastrointestinal bleeding in such patients have been studied. The decreased amount of von Willebrand factor polymers is now recognized as one of the most common causes of increased incidence of gastrointestinal bleeding in patients with left ventricular assist devices alongside increased arteriovenous malformations. Multiple treatment modalities have been identified to prevent and treat gastrointestinal bleeding in these patients. Since the use of left ventricular assist devices is becoming more prevalent in patients with advanced heart failure, we decided to conduct this systematic review. The article summarizes the incidence, pathophysiology, and management of lower gastrointestinal bleeding in patients with left ventricular assist devices.

Echocardiographic indices of left ventricular function and filling pressure are not related to blood pool activity on pyrophosphate scintigraphy.

BACKGROUND: Pyrophosphate (PYP) imaging has a high diagnostic accuracy for transthyretin cardiac amyloidosis (ATTR-CA). Indeterminate findings are often reported due to persistent blood pool activity, presumed to be from low cardiac output. We evaluated the relationship between blood pool activity on PYP imaging and echocardiographic indices of cardiac function. METHODS: Clinical and imaging data of 189 patients referred for PYP scintigraphy were evaluated. All patients underwent planar imaging and SPECT (diagnostic standard). Among those with a negative PYP SPECT, persistent left ventricular blood pool activity on planar images was inferred by a visual score ≥2 or a heart-to-contralateral (HCL) ratio ≥ 1.5. Absence of blood pool activity was inferred when both visual score was < 2 and HCL was < 1.5. Left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), stroke volume index (SVi), and left atrial pressure (LAP) were calculated from standard transthoracic echocardiograms. RESULTS: ATTR-CA was present in 43 (23%) patients. Among those with a negative PYP SPECT, 11 patients had significant blood pool activity. Patients with ATTR-CA had a lower LVEF, SVi, and GLS, with a higher LAP, compared to those without ATTR-CA. Among those without ATTR-CA, there were no significant differences in these parameters. CONCLUSION: Approximately 8% of patients with a negative PYP SPECT have significant blood pool activity. Measures of cardiac function are not different among those with and without blood pool activity. PYP SPECT should be routinely performed in all patients to avoid false image interpretation.

Multimodality imaging for diagnosis of subclinical hereditary transthyretin cardiac amyloidosis.

We present a case of a patient with worsening visual acuity and dense vitreal debris who was found to have vitreal transthyretin amyloid (ATTR) infiltration. Cardiac workup, performed to identify systemic amyloidosis, demonstrated focal myocardial amyloid infiltration on pyrophosphate (PYP) scintigraphy and cardiac magnetic resonance (CMR), resulting in a diagnosis of subclinical ATTR cardiac amyloidosis (ATTR-CA). Patient was identified as a carrier of p.S70R mutation which results in an aggressive ATTR phenotype. Patient is tolerating transthyretin silencer therapy well. Through this case, we discuss the role of a multimodality imaging approach for the diagnosis of subclinical ATTR-CA.

Myocardial ischemia in patients with large prior infarction: Clinical decision making and review of literature.

Myocardial perfusion imaging (MPI) with single photon emission computed tomography (SPECT) or positron emission tomography (PET) is a widely used technique for the evaluation of coronary artery disease (CAD). Interpreting physicians rely on regional variations in myocardial radiotracer uptake between rest and stress images to identify hemodynamically significant epicardial coronary artery stenosis. However, interpretation of MPI is very difficult in patients with large infarcts where there is no scintigraphically normal reference myocardium for comparison. In these patients, the stress and rest images appear similar due to balanced ischemia in the non-infarct territory. There are no clear guidelines on how to approach these cases. We present a case of MPI with a large right coronary artery territory (RCA) infarct where the left main (LM) coronary artery territory has no relative comparator and the images looked the same on stress and rest. However, the patient had multiple high-risk ancillary findings including electrocardiographic (ECG) changes with regadenoson, transient ischemic dilatation (TID), large severe inferior infarct, low myocardial blood flow (MBF) and myocardial flow reserve (MFR), but most notably increased right ventricular (RV) uptake on the stress images that was a subtle clue that we were dealing with LM equivalent in non-infarct zone. The coronary angiogram confirmed our findings. Through our case, we provide a comprehensive approach and review of literature on how to approach such challenging encounters.

Mechanical pulmonic valve thrombosis: expanding role of cardiac CT and multimodality imaging.

We report a case of a 44-year-old man with a clinical history of Tetralogy of Fallot status post staged surgical correction with mechanical pulmonic valve replacement who presented with progressive exertional dyspnea in the setting of non-compliance with anticoagulation. In the context of this suggestive clinical presentation, the diagnosis of mechanical pulmonic valve thrombosis (MPVT) was made possible via multimodality imaging, including transthoracic echocardiogram and cardiac computed tomography angiography. Due to the uncommon nature of the condition, the patient was treated with systemic thrombolysis and anticoagulation using evidence-based guidelines, largely extrapolated from left-sided mechanical valve thrombosis. Our case underscores the importance of anticoagulation in MPVT and recognizing the features of MPVT on clinical history, physical examination, and multimodality imaging. It is essential to understand the pivotal role of multimodality imaging in the assessment of MPVT and realize the limitations of available data regarding the management of MPVT in the current era.

Mixing effects of three Eurasian plants on root decomposition in the existence of living plant community in a meadow steppe.

In grasslands, roots of different plant species decay in combination in the presence of living plants, besides, most root decomposition studies are conducted on how roots of plants decomposed alone or in artificial compositions in the absence of living plants. Therefore, we evaluated how roots of different perennial plants induced effects on decomposition process under living plants and their associated mechanisms. By using litter bag technique, we determined the root decomposition process of three perennial plants, Leymus chinensis, Phragmites australis, and Kalimeris integrifolia grown in monocultures, bi- and tri-species mixtures, after 12 months of incubation under living plants and bare soil communities. We found both additive and non-additive effects on decomposition dynamics indicating that root mass losses of compositions cannot be calculated from decaying rates of individual species. The rich-nutrient roots of K. integrifolia in monocultures and in mixtures with other plant species decayed faster. Compared with bare soil, microbial activities were enhanced under living plant communities and hence stimulated decomposition rates. Our results indicated that microbial activities are important but secondary factors to root physico-chemical properties impacting root decomposition rates. In conclusion, the empirical relationships developed here are helpful to better understand the effects of root properties and microbial activities on decay rates.

Asystole following Regadenoson administration: Review of literature, risk factors and management.

Regadenoson, a selective A2A receptor agonist, is widely used for vasodilator stress myocardial perfusion imaging and has a superior adverse effect profile when compared with other agents. However, with widespread use, there have been several reported cases of Regadenoson induced bradyarrhythmias and even asystole in patients with no known conduction system disease. In this article, we report a case of asystole following Regadenoson administration, evaluate mechanisms and risk factors for Regadenoson induced bradyarrhythmias to better identify patients at risk. We also review the available treatment options and propose recommendations for limiting its risk.

Comparison of planar with tomographic pyrophosphate scintigraphy for transthyretin cardiac amyloidosis: Perils and pitfalls.

BACKGROUND: Tc-99m pyrophosphate (PYP) SPECT is recommended for indeterminate findings on planar imaging. We aimed to compare the findings on planar PYP scintigraphy alone to that of routinely performed PYP SPECT. METHODS: PYP scintigraphy data of 133 patients (53% men; mean age 76 years) were evaluated. SPECT was routinely performed following 1-hour planar imaging, in all cases. Semiquantitative visual score and heart-to-contralateral (H/CL) ratio were determined in all patients as recommended. RESULTS: PYP images from 35 patients (26%) were considered to be positive based on SPECT myocardial uptake. Among them, 20 (57%) had a H/CL ratio ≥1.5 and 34 had a visual score ≥ 2. SPECT identified myocardial uptake in one patient with a visual score < 2 and refuted the presence of myocardial uptake in two patients with a visual score ≥ 2. Visual score correlated well with SPECT (r = 0.94; P < .0001) and had an accuracy of 98% for tomographic myocardial uptake. Addition of H/CL ratio reduced the diagnostic performance of visual score. CONCLUSIONS: Planar-derived visual score has an excellent accuracy for tomographic myocardial uptake, though it misclassifies a small proportion of patients. H/CL ratio decreases the diagnostic certainty of planar imaging. Tomographic imaging prevents misdiagnoses and should always be performed.

Acute Pericarditis and Cardiac Tamponade in a Patient with COVID-19: A Therapeutic Challenge.

We report a case of acute viral pericarditis and cardiac tamponade in a patient with COVID-19 to highlight the associated treatment challenges, especially given the uncertainty associated with the safety of standard treatment. We also discuss complications associated with delayed diagnosis in patients who potentially may need mechanical ventilation. LEARNING POINTS: Large pericardial effusion and cardiac tamponade should be considered in patients with COVID-19 who decompensate further after intubation and mechanical ventilation.The characteristics of pericardial effusion in patients with COVID-19 are described.A successful treatment approach for acute pericarditis in a patient with COVID-19 in light of differing opinions over the safety of NSAID use is described.

Transient ST Segment Elevation in Two Patients with COVID-19 and a Normal Transthoracic Echocardiogram.

We continue to learn about cardiac involvement in patients with COVID-19. These patients can develop acute coronary syndrome and severe myocarditis with a reduced ejection fraction. We describe two critically ill COVID-19 patients who developed ST elevation that resolved on repeat ECG without any intervention. LEARNING POINT: ST elevation may occur in critically ill COVID-19 patients.

Ruptured Sinus of Valsalva Aneurysm Causing Aorto-Atrial Fistula and Acute Heart Failure: A Rare Encounter.

A ruptured sinus of Valsalva aneurysm as a cause of aorto-atrial fistula is very rare. We present the case of a 53-year-old female who presented with symptoms of acute heart failure and suspicion of an aorto-atrial fistula found on a transthoracic echocardiogram, which was confirmed on transesophageal echocardiography. A coronary angiogram showed normal coronary arteries but confirmed the right aorto-atrial fistula on aortogram. She underwent successful surgical repair of the fistula. Her postoperative echocardiogram showed a normal right atrium and right ventricle with no shunt. A ruptured sinus of Valsalva aneurysm is a devastating event and presents as acute heart failure. Prompt diagnosis and surgical repair is necessary to prevent mortality. LEARNING POINTS: A ruptured sinus of Valsalva aneurysm causing an aorto-atrial fistula can present as acute heart failure.A transthoracic echocardiogram can identify the presence and location of a sinus of Valsalva aneurysm, while a transesophageal echocardiogram can recognize fistulous tract formation. Cardiac magnetic resonance imaging and computed tomography can confirm or better categorize echocardiographic findings.The management of an aorto-atrial fistula is surgical intervention, involving a patch repair.

Correction: Lidocaine-Induced Systemic Toxicity: A Case Report and Review of Literature.

[This corrects the article DOI: 10.7759/cureus.1275.].

Community-acquired Pneumonia with Methicillin-resistant Staphylococcus Aureus in a Patient Admitted to the Intensive Care Unit: A Therapeutic Challenge.

Methicillin-resistant Staphylococcus aureus (MRSA) was previously considered a purely nosocomial pathogen. However, community-acquired MRSA has recently emerged as an important cause of severe necrotizing community-acquired pneumonia (CA-MRSA) in previously healthy individuals. This new pathogen exhibits antibiotic resistance and is linked to extended hospital stay and higher mortality. CA-MRSA has presented new therapeutic challenges due to high vancomycin treatment failure and lack of specificity of clinical findings. There is emerging evidence that treatment with linezolid leads to better patient outcomes in patients with CA-MRSA. Through this case, we aim to raise awareness about early institution of therapy for CA-MRSA whenever it is suspected, to improve patient outcomes.

Colovesical Fistula: An Unusual Complication of Cytomegalovirus Colitis.

Cytomegalovirus (CMV) is a double-stranded DNA virus that is associated with clinically significant disease in patients with advanced immunosuppression, particularly those with human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). End-organ disease with CMV is classically associated with a CD4 cell count less than 50 cells/microliter. CMV colitis is the second most common manifestation of end-organ disease in this patient population. CMV-associated enteric fistula is a rare complication that has been described in only a few case reports in the literature. These cases describe gastrocolic, enterocutaneous, enterocolic, rectovaginal, and colocutaneous fistulae. However, colovesical fistula has not been described previously. Here, we report the first case of CMV-associated colovesical fistula in a patient with HIV infection and AIDS.

Immune Reconstitution Inflammatory Syndrome Associated Thrombocytopenia in a Patient with Human Immunodeficiency Virus Infection: A Rare Hematological Manifestation.

Human immunodeficiency virus (HIV) associated thrombocytopenia was commonly encountered in the era prior to the advent of antiretroviral therapy (ART). With the widespread use of ART, its incidence has significantly declined. Immune reconstitution inflammatory syndrome (IRIS) is an immune dysregulation phenomenon that reveals itself clinically as paradoxical deterioration after the commencement of ART in HIV infected patients. It has a wide variety of clinical manifestations. However, hematologic involvement is rare. Here, we present a very rare case of IRIS associated thrombocytopenia. With this case we intend to create mindfulness of the possibility of IRIS being one of the explanations for thrombocytopenia.