Dysautonomic responses during percutaneous carotid intervention: principles of physiology and management.

Percutaneous carotid artery stenting (CAS) has emerged as a less invasive alternative to carotid endarterectomy for the treatment of carotid atherosclerotic disease. The main risk of CAS is the occurrence of neuro-vascular complications; however, carotid artery stenting-related dysautonomia (CAS-D) (hypertension, hypotension, and bradycardia) is the most frequently reported problem occurring in the periprocedural period. Alterations in autonomic homeostasis result from baroreceptor stimulation, which occurs particularly at the time of balloon inflation in the region of the carotid sinus. The response can be profound enough to induce asystole or even complete cessation of postganglionic sympathetic nerve activity. Frequency and factors predisposing a patient to CAS-D have been investigated in several studies; however, there are significant discrepancies in results among reports. Lack of consistent findings may arise from using different methods and definitions, as well as other factors discussed in detail in this review. Furthermore, a correlation of CAS-D with short and long-term outcomes has been investigated only in small and mostly retrospective studies, explaining why its prognostic significance remains uncertain. In this manuscript, we have focused on risk factors, pathophysiology and management of periprocedural autonomic dysfunction. As there is no standardized approach to the treatment of CAS-D, we present an algorithm for the periprocedural management of patients undergoing CAS. The proposed algorithm was developed based on our procedural experience as well as data from the available literature. The Yale Algorithm was successfully implemented at our institution and we are currently collecting data for short- and long-term safety. © 2014 Wiley Periodicals, Inc.

Management of Hypertension in Patients with Ischemic Heart Disease.

Ischemic heart disease (IHD) affects about 16 million adults in the USA. Many more individuals likely harbor subclinical coronary disease. Hypertension (HTN) continues to be a potent and widespread risk factor for IHD. Among other Framingham risk factors of tobacco use, diabetes mellitus, dyslipidemia, and left ventricular hypertrophy, HTN plays an independent role in augmenting IHD risk, as well as a multiplicative role with respect to adverse outcomes when HTN is present concurrently with the other major IHD risk factors listed above. Over the past two decades, numerous studies and guideline reports have been presented with the aims of (a) elucidating the pathophysiology of IHD, (b) delineating an ideal blood pressure (BP) threshold at which to institute pharmacotherapy, and (c) defining the optimal pharmacologic elements of a therapeutic regimen. While there are active debates surrounding the existence and relevance of the J curve in IHD patients who have HTN, as well as the numerical level of the BP cutoff justifying drug therapy in the general population, there is a general consensus that the BP target in IHD patients should be lower than 140/90 mmHg. The most appropriate class (or classes) of medication recommended will depend on the comorbid conditions associated with each individual patient. Overall, however, there is no major evidence underscoring a significant difference between drug classes, provided the target BP is achieved, although it should be pointed out that the most recent (2015) American Heart Association (AHA)/American College of Cardiology (ACC)/American Society of Hypertension (ASH) guideline statement now elevates beta-blockers (BB) to the same level of recommendation as other classes of hypertension drugs in the treatment of patients who have hypertension and ischemic heart disease. Although most agents that reduce blood pressure will correspondingly lower myocardial workload, BB may exhibit a special advantage in IHD patients because BB (as well as verapamil and diltiazem subclasses of calcium channel blockers or CCB) act to lower HR as well as cardiac inotropy. Moreover, BB will remain an integral if not indispensable part of the management of IHD, especially in those with history of angina pectoris or MI, based on decades of favorable clinical as well as trial experience. This extensive salutary historical background has served as a foundation for the 2015 committee's decision to bring BB into the front rank of BP agents for those hypertensive individuals suffering simultaneously from IHD.

Cellularity and structure of fresh human coronary thrombectomy specimens; presence of cells with markers of progenitor cells.

Acute coronary syndromes and acute myocardial infarctions are often related to plaque rupture and the formation of thrombi at the site of the rupture. We examined fresh coronary thrombectomy specimens from patients with acute coronary syndromes and assessed their structure and cellularity. The thrombectomy specimens consisted of platelets, erythrocytes and inflammatory cells. Several specimens contained multiple cholesterol crystals. Culture of thrombectomy specimens yielded cells growing in various patterns depending on the culture medium used. Culture in serum-free stem cell enrichment medium yielded cells with features of endothelial progenitor cells which survived in culture for a year. Immunohistochemical analysis of the thrombi revealed cells positive for CD34, cells positive for CD15 and cells positive for desmin in situ, whereas cultured cell from thrombi was desmin positive but pancytokeratin negative. Cells cultured in endothelial cell medium were von Willebrand factor positive. The content of coronary thrombectomy specimens is heterogeneous and consists of blood cells but also possibly cells from the vascular wall and cholesterol crystals. The culture of cells contained in the specimens yielded multiplying cells, some of which demonstrated features of haematopoietic progenitor cells and which differentiated into various cell-types.

Direct current cardioversion-triggered atypical Tako-tsubo cardiomyopathy: a case report and review of literature.

Background: Tako-tsubo stress cardiomyopathy is a clinical syndrome marked by transient reduction of left ventricular function in the setting of emotional or physical stress and in the absence of obstructive coronary artery disease. We describe a case of an atypical variant of Tako-tsubo in a male patient following an elective direct current cardioversion (DCCV). Case summary: A 78-year-old male whose atrial fibrillation persisted after earlier unsuccessful direct current DCCV and radiofrequency ablations presented to the emergency department for acutely worsening dyspnoea and orthopnoea 12 h following his most recent DCCV. Previously, he was known to have non-obstructive coronary artery disease. Evaluation was notable for troponin I 0.019 ng/mL (negative <0.050 ng/mL), pro-brain natriuretic peptide 2321 pg/mL (reference range 0.0-900 pg/mL). There were no acute electrocardiogram abnormalities. He required bilevel positive airway pressure but was weaned off eventually to room air. Transthoracic echocardiogram revealed newly reduced left ventricular ejection fraction of 45-50%, associated with hypokinesis of the basal anteroseptal segment, as well as akinesis of mid-inferoseptal and mid-anteroseptal segments. Apical contractility was preserved. On Day 5 of hospitalization, diagnostic left heart catheterization again revealed benign coronary anatomy, and he was discharged home the following day. Discussion: Only five other cases of cardioversion mediated Tako-tsubo cardiomyopathy have been reported in the literature. To our knowledge, this is the first case of DCCV-induced atypical Tako-tsubo cardiomyopathy. Although overall prognosis is favourable, some have been observed to require advanced support therapy. Given risk for life-threatening complications, patients undergoing cardioversion should be educated on symptoms of congestive cardiomyopathy.

Aortic remodeling and competitive flow after surgical treatment of aortic dissection.

Aortic remodeling after dissection is poorly understood and remains a focus of current research. In the present report, we have described the cases of two patients with acute lower extremity ischemia related to malperfusion from aortic dissection treated with extra-anatomic axillobifemoral bypass. During long-term follow-up, aortic remodeling led to reinstitution of flow through the native aorta. This resulted in competitive flow, leading to complete thrombosis of the extra-anatomic conduits. These cases highlight the occurrence of spontaneous aortic recanalization and subsequent competitive flow, two vascular phenomena that are not well understood but can significantly affect patient outcomes.

Secondary hypertension: obesity and the metabolic syndrome.

The epidemic of obesity in the United States and around the world is intensifying in severity and scope and has been implicated as an underlying mechanism in systemic hypertension. Obese hypertensive individuals characteristically exhibit volume congestion, relative elevation in heart rate, and high cardiac output with concomitant activation of the renin-angiotensin-aldosterone system. When the metabolic syndrome is present, insulin resistance and hyperinsulinemia may contribute to hypertension through diverse mechanisms. Blood pressure can be lowered when weight control measures are successful, using, for example, caloric restriction, aerobic exercise, weight loss drugs, or bariatric surgery. A major clinical challenge resides in converting short-term weight reduction into a sustained benefit. Pharmacotherapy for the obese hypertensive patient may require multiple agents, with an optimal regimen consisting of inhibitors of the renin-angiotensin-aldosterone system, thiazide diuretics, beta-blockers, and calcium channel blockers if needed to attain contemporary blood pressure treatment goals.

Distal embolic protection during renal artery stenting: impact on hypertensive patients with renal dysfunction.

Distal embolic protection (DEP) may prevent embolization of atherosclerotic debris during renal artery stenting. The authors retrospectively identified 48 hypertensive patients with chronic kidney disease (CKD) who underwent renal artery stenting between 2002 and 2005 and compared stenting alone (n=17) to stenting/DEP (n=31). Blood pressure (BP) and estimated glomerular filtration rate (eGFR) (mL/min/1.73m(2)) at baseline at 6 and 12 months were compared. Overall, eGFR improved by 4.7 (P=.005) at 6 months and 3.8 (P=.003) at 12 months compared with baseline. Comparing stent to stent/DEP patients, eGFR improvement did not differ at 6 months (7.6 vs 2.9; P=.15) or at 12 months (4.4 vs 3.5; P=.74). Systolic BP reduction was similar between stent and stent/DEP patients at 6 months (-9 vs -14 mm Hg; P=.59) and at 12 months (-18 vs -16 mm Hg; P=.89). Renal artery stenting improved eGFR and systolic BP in patients with hypertension and CKD; however, DEP did not enhance these effects.

Free-wall rupture of the myocardium following infarction: a changing clinical portrait in the reperfusion era: a case report.

Free wall rupture of the myocardium is an important complication and major cause of death following acute transmural (ST segment elevation) myocardial infarction. Pathologic changes on a cellular level may combine with mechanical stressors to weaken the myocardium postinfarction. Risk factors for myocardial rupture include advanced age, female gender, prior hyper-tension, first myocardial infarction, late presentation, lack of collateral blood flow, and persisting chest pain and ST segment elevations. Thrombolytic therapy does not increase risk of rupture when given early in myocardial infarction, but late thrombolytic therapy may heighten risk. Primary percutaneous coronary intervention for acute myocardial infarction has reduced the incidence of myocardial rupture compared to thrombolytic therapy. This advantage likely can be ascribed to higher rates of immediate reperfusion with catheter techniques, as well as to the avoidance of thrombolytic-mediated hemorrhagic transformation of the infarction zone. Careful regulation of blood pressure and pulse using nitrates and beta-adrenergic blockers may mitigate the tendency toward myocardial rupture. Early and accurate diagnosis based on clinical and echocardiographic evidence can lead to successful surgical treatment.

Angiosarcoma in a pregnant woman presenting with pericardial tamponade--a case report and review of the literature.

Although asymptomatic pericardial effusions are relatively common in pregnancy, their true incidence is not known. Symptomatic effusions are, however, rare in pregnancy. The authors present a rare case of pericardial tamponade complicating pregnancy with resulting diagnosis of angiosarcoma. They review the literature involving pericardial disease in pregnancy and discuss important issues in management and include a discussion of angiosarcoma.

Insulin-sensitizing antihyperglycemic drugs and mortality after acute myocardial infarction: insights from the National Heart Care Project.

OBJECTIVE: Thiazolidinediones (TZDs) and metformin are insulin-sensitizing antihyperglycemic agents with reported benefits on atherosclerosis. Despite extensive use in patients with diabetes and cardiovascular disease, there is a paucity of outcomes data with metformin and none yet with TZDs. We sought to determine the impact of these insulin sensitizers on outcomes in diabetic patients after hospitalization with acute myocardial infarction (AMI). RESEARCH DESIGN AND METHODS: We conducted a retrospective cohort study of 24,953 Medicare beneficiaries with diabetes discharged after hospitalization with AMI between April 1998 and March 1999 or July 2000 and June 2001. The independent association between discharge prescription for metformin, TZD, or both agents and outcomes at 1 year was assessed in multivariable Cox proportional hazards models, adjusting for patient, physician, and hospital variables. The primary outcome was time to death within 1 year of discharge; secondary outcomes were time to first rehospitalization within 1 year of discharge for AMI, heart failure, and all causes. RESULTS: There were 8,872 patients discharged on an antihyperglycemic agent, of which 819 were prescribed a TZD, 1,273 metformin, and 139 both drugs. After multivariable analysis, compared with patients prescribed an antihyperglycemic regimen that included no insulin sensitizer, mortality rates were not significantly different in patients treated with either metformin (hazard ratio [HR] 0.92 [95% CI 0.81-1.06]) or a TZD (0.92 [0.80-1.05]) but were lower in those prescribed both drugs (0.52 [0.34-0.82]). The results were similar among patients with heart failure. The prescription of a TZD was associated with a borderline higher risk of all-cause readmission (1.09[1.00-1.20]), predominately due to a higher risk for heart failure readmission (1.17 [1.05-1.30]). CONCLUSIONS: Individually, prescription of insulin-sensitizing drugs is not associated with a significantly different risk of death in older diabetic patients within 1 year following AMI compared with other antihyperglycemic agents. Combined, however, metformin and TZDs may exert benefit. TZD prescription is associated with a higher risk of readmission for heart failure after myocardial infarction.

Hemorrhagic pheochromocytoma associated with systemic corticosteroid therapy and presenting as myocardial infarction with severe hypertension.

Pheochromocytomas classically present with paroxysms of hypertension and adrenergic symptoms including headaches, palpitations, tremor, and anxiety. However, these tumors can be clinically silent and occasionally present only when catecholamine release is up-regulated by exogenous stimuli. In addition, the clinical presentation of pheochromocytoma can mimic a number of more common medical conditions, including migraine headaches, cardiac arrhythmias, and myocardial infarction, making diagnosis difficult. In this report, we present the case of a young woman who, while receiving oral corticosteroid therapy for presumed migraine headaches, suffered a myocardial infarction and ultimately hemorrhaged into a previously undiagnosed pheochromocytoma. Our patient exhibited severe, labile hypertension after the administration of iv beta-blockade for presumed myocardial ischemia, raising our initial clinical suspicion for pheochromocytoma. In this paper we review some of the key clinical issues related to this complex case, including steroid-induced stimulation of catecholamine synthesis and release, the role of pheochromocytoma in myocardial ischemia and electrocardiographic changes, and the rare complication of tumor hemorrhage. We then briefly review the essential diagnostic and management strategies for this rare but potentially lethal tumor, with specific emphasis on pheochromocytoma-related cardiovascular emergencies and the surgical management of tumor hemorrhage.

Multi-drug-resistant hypertension caused by severe aortic coarctation presenting in late adulthood.

Aortic coarctation, a congenital narrowing in the region of the ligamentum arteriosium, is a rare etiology for multi-drug-resistant hypertension in adulthood; however, advances in stenting modalities may offer long-term improvements in morbidity and possibly even cure. We report on a female patient in her late 50s presenting with refractory hypertension and severely elevated renin levels, ultimately diagnosed with aortic coarctation and treated with percutaneous stent implantation, which resulted in successful blood pressure control with verapamil monotherapy. This case highlights the efficacy of endovascular stent implantation for the treatment of coarctation and the need for clinicians to consider this disease entity in the differential diagnosis of refractory hypertension even in late adulthood.

Comparison of coronary artery specific leukocyte-platelet conjugate formation in unstable versus stable angina pectoris.

This study evaluates transcoronary changes in neutrophil and platelet activation and conjugate formation in patients with angina pectoris secondary to coronary artery disease. We examined parameters of neutrophil and platelet activation as well as the neutrophil-platelet conjugate formation in patients who underwent diagnostic coronary angiography. Thirty-nine patients with chest pain referred for cardiac catheterization were studied (23 patients with unstable angina pectoris [UAP] and 16 with stable angina pectoris [SAP]). Before coronary angiography, blood samples were obtained simultaneously from the aortic root and coronary sinus to assess leukocyte (CD11b) and platelet (CD62P) activation and leukocyte-platelet conjugates. There was a 94% increase in CD62-expressing platelets from the aorta to the coronary sinus in patients with UAP compared with a 49% increase in patients with SAP. The percentage of neutrophil-platelet conjugates increased by 22% in patients with UAP compared with a 16% decrease in those with SAP (p <0.01). In contrast, monocyte-platelet binding across the coronary bed increased to a similar degree in both groups. This study demonstrates an increase in neutrophil-platelet conjugates across the coronary circulation in UAP, compatible with a higher activation state in both cell types.

The renin-angiotensin-aldosterone system: cardiorenal effects and implications for renal and cardiovascular disease states.

The renin-angiotensin-aldosterone system (RAAS) plays an integral role in maintaining vascular tone, optimal salt and water homeostasis, and cardiac function in humans. However, it has been recognized in recent years that pathologic consequences may also result from overactivity of the RAAS. Clinical disease states such as renal artery stenosis, hypertension, diabetic and nondiabetic nephropathies, left ventricular hypertrophy, coronary atherosclerosis, myocardial infarction, and congestive heart failure (CHF) are examples. Part of the adverse cardiorenal effects of the RAAS may be related to the prominent role that this system plays in the activation of the sympathetic nervous system, the dysregulation of endothelial function and progression of atherosclerosis, as well as inhibition of the fibrinolytic system. Also, direct profibrotic actions of angiotensin II and aldosterone in the kidney and heart promote end organ injury. Current basic science and clinical research supports the use of inhibitors of the RAAS, including angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists in treating hypertension, improving diabetic nephropathy and other forms of chronic kidney disease, preventing or ameliorating CHF, and optimizing prognosis after myocardial infarction.

Spontaneous coronary artery dissection in a woman receiving 5-fluorouracil--a case report.

A 39-year-old woman with cervical cancer treated with pelvic radiation therapy and 5-fluorouracil (5-FU) was hospitalized for dehydration and intractable vomiting. She developed an acute ST-elevation myocardial infarction (MI) that extended electrocardiographically after thrombolytic therapy. Coronary angiography demonstrated a completely occluded left anterior descending (LAD) artery with extensive coronary dissection that was treated successfully with stenting. The authors discuss several factors that may have contributed to the spontaneous coronary artery dissection (SCAD) including chemotherapy-induced vasospasm, hemodynamic stress of vomiting, and hormonal changes associated with pelvic radiation.

Metformin and thiazolidinedione use in Medicare patients with heart failure.

CONTEXT: According to package inserts, metformin is contraindicated in diabetic patients receiving drug treatment for heart failure therapy, and thiazolidinediones are not recommended in diabetic patients with symptoms of advanced heart failure. Little is known about patterns of use of these antihyperglycemic drugs in diabetic patients with heart failure. OBJECTIVE: To determine the proportions of patients hospitalized with heart failure and concomitant diabetes treated with metformin or thiazolidinediones. DESIGN: Serial cross-sectional measurements using data from retrospective medical record abstraction. SETTING: Nongovernmental acute care hospitals in the United States. PATIENTS: Two nationally representative samples of Medicare beneficiaries hospitalized with the primary diagnosis of heart failure and concomitant diabetes between April 1998 and March 1999 and between July 2000 and June 2001. MAIN OUTCOME MEASURES: The prescription of either metformin or a thiazolidinedione at hospital discharge. RESULTS: In the 1998-1999 sample (n = 12 505), 7.1% of patients were discharged with a prescription for metformin, 7.2% with a prescription for a thiazolidinedione, and 13.5% with a prescription for either drug. In the 2000-2001 sample (n = 13 158), metformin use increased to 11.2%, thiazolidinedione use to 16.1%, and use of either drug to 24.4% (P<.001 for all comparisons). Similar increases were seen among patients of all age groups, all races, and both sexes. CONCLUSIONS: The use of metformin and thiazolidinediones is common and has increased rapidly in Medicare beneficiaries with diabetes and heart failure in direct contrast with explicit warnings against this practice by the Food and Drug Administration. Further studies to establish the safety and effectiveness of this practice are needed to ensure optimal care of patients with diabetes and heart failure.

Impact of baseline renal function on outcomes of renal artery stenting in hypertensive patients.

Renal artery stenting may improve blood pressure (BP) and renal function in resistant hypertension patients; however, benefit may differ depending on the degree of renal dysfunction. The authors analyzed 67 consecutive patients receiving stenting for obstructive renal artery disease between 2002 and 2005. Patients were categorized as normal or mildly impaired according to estimated glomerular filtration rate (eGFR) (> or =60 mL/min/1.73 m(2)), moderately impaired (eGFR 30 to 59 mL/min/1.73 m(2)), and severely impaired (eGFR <30 mL/min/1.73 m(2)). In patients with eGFR > or =60, systolic BP did not significantly improve from baseline. However, in patients with an eGFR between 30 and 59 mL/min/1.73 m(2), systolic BP decreased by 12 mm Hg at 6 months (P=.02) and 14 mm Hg at 12 months (P=.01). Greater benefit was observed in patients with eGFR <30 mL/min/1.73 m(2), with a 16 mm Hg (P=.10) and 21 mm Hg (P=.02) decrease at 6 and 12 months, respectively. Renal function was stable across all groups. Renal artery stenting reduced BP and produced greatest benefit in patients with baseline impaired renal function.

Anabolic steroids, acute myocardial infarction and polycythemia: a case report and review of the literature.

The association between testosterone-replacement therapy and cardiovascular risk remains unclear with most reports suggesting a neutral or possibly beneficial effect of the hormone in men and women. However, several cardiovascular complications including hypertension, cardiomyopathy, stroke, pulmonary embolism, fatal and nonfatal arrhythmias, and myocardial infarction have been reported with supraphysiologic doses of anabolic steroids. We report a case of an acute ST-segment elevation myocardial infarction in a patient with traditional cardiac risk factors using supraphysiologic doses of supplemental, intramuscular testosterone. In addition, this patient also had polycythemia, likely secondary to high-dose testosterone. The patient underwent successful percutaneous intervention of the right coronary artery. Phlebotomy was used to treat the polycythemia acutely. We suggest that the chronic and recent "stacked" use of intramuscular testosterone as well as the resultant polycythemia and likely increased plasma viscosity may have been contributing factors to this cardiovascular event, in addition to traditional coronary risk factors. Physicians and patients should be aware of the clinical consequences of anabolic steroid abuse.