Impact of temperature and atmospheric pressure on the incidence of major acute cardiovascular events.

BACKGROUND: The impact of meteorological conditions on the occurrence of various cardiovascular events has been reported internationally. Data about the Dutch situation are limited. OBJECTIVES: We sought to find out a correlation between weather conditions and the incidence of major acute cardiovascular events such as type A acute aortic dissection (AAD), acute myocardial infarction (AMI) and acutely presented abdominal aortic aneurysms (AAAA). METHODS: Between January 1998 and February 2010, patients who were admitted to our hospital (Catharina Hospital, Eindhoven, the Netherlands) because of AAD (n = 212), AMI (n = 11389) or AAAA (n = 1594) were registered. These data were correlated with the meteorological data provided by the Royal Dutch Meteorological Institute (KNMI) over the same period. RESULTS: During the study period, a total number of 11,412 patients were admitted with AMI, 212 patients with AAD and 1593 patients with AAAA. A significant correlation was found between the daily temperature and the number of hospital admissions for AAD. The lower the daily temperature, the higher the incidence of AAD (p = 0.002). Lower temperature was also a predictor of a higher incidence of AMI (p = 0.02). No significant correlation was found between daily temperature and onset of AAAA. CONCLUSIONS: Cold weather is correlated with a higher incidence of AAD and AMI.

Giant cell arteritis as a cardiovascular entity.

Giant cell arteritis (GCA) is a relatively infrequent disorder that is underdiagnosed and little appraised in the field of general cardiology. However, it is important to be familiar with the clinical picture of this disease, especially because of the risk of developing fatal aortic aneurysms. If the disease is suspected after a thorough history and clinical examination combined with laboratory investigation, the diagnosis can be confirmed with (18)F-2-deoxy-glucose positron emission tomographic (FDG-PET) imaging. Early recognition of giant cell arteritis followed by prompt treatment with glucocorticosteroids will decrease the risk of developing large-vessel complications. (Neth Heart J 2009;17:281-3.).

Intra-thoracic blood volume measurement by contrast magnetic resonance imaging.

The intra-thoracic blood volume (ITBV) is a cardiovascular parameter related to the cardiac preload and left ventricular function. Its assessment is, therefore, important for diagnosis and follow-up of several cardiovascular dysfunctions. Nowadays, the ITBV can be accurately measured only by invasive indicator dilution techniques, which require a double catheterization of the patient. In this study, a novel technique is presented for ITBV assessment by dynamic magnetic resonance imaging after intravenous injection of a small bolus of gadolinium chelate. The dose was chosen on the basis of in vitro calibration. The bolus first pass is detected from a simultaneous dynamic image series of the right and left ventricles. Two indicator dilution curves are derived and used to inspect the transpulmonary dilution system. Various mathematical models for the interpretation of the measured indicator dilution curves are compared. The ITBV is assessed as the product of the transpulmonary mean transit time of the indicator and the cardiac output, obtained by phase contrast magnetic resonance angiography. In vitro measurements showed a correlation coefficient larger than 0.99 and preliminary tests with volunteers proved the feasibility of the method, opening new possibilities for noninvasive quantitative cardiovascular diagnostics.

Guidelines for heart transplantation.

Based on the changes in the field of heart transplantation and the treatment and prognosis of patients with heart failure, these updated guidelines were composed by a committee under the supervision of both the Netherlands Society of Cardiology and the Netherlands Association for Cardiothoracic surgery (NVVC and NVT).THE INDICATION FOR HEART TRANSPLANTATION IS DEFINED AS: 'End-stage heart disease not remediable by more conservative measures'.CONTRAINDICATIONS ARE: irreversible pulmonary hypertension/elevated pulmonary vascular resistance; active systemic infection; active malignancy or history of malignancy with probability of recurrence; inability to comply with complex medical regimen; severe peripheral or cerebrovascular disease and irreversible dysfunction of another organ, including diseases that may limit prognosis after heart transplantation.Considering the difficulties in defining end-stage heart failure, estimating prognosis in the individual patient and the continuing evolution of available therapies, the present criteria are broadly defined. The final acceptance is done by the transplant team which has extensive knowledge of the treatment of patients with advanced heart failure on the one hand and thorough experience with heart transplantation and mechanical circulatory support on the other hand. (Neth Heart J 2008;16:79-87.).

ACS, myocardial bridging, Tako-tsubo syndrome and mitral regurgitation.

Isolated systolic compression of the mid portion of the left anterior descending artery (LAD) by a bridge of overlying cardiac muscle is an infrequent but well-recognised angiographic anomaly that is often considered harmless. The long-term prognosis appears to be excellent, but occasional reports of patients with angina pectoris, myocardial infarction and sudden death indicate that this is not always true. The prevalence of the anomaly in the normal population is unknown, but the incidence is low and ischaemic events are rare. Tako-tsubo-like left ventricular dysfunction syndrome (TTS) is characterised by ischaemia, anterior ST-segment elevation, no significant coronary artery disease and reversible ampulla-like left ventricular ballooning in postmenopausal females after emotional or physical stress. Dynamic left ventricular outflow tract (LVOT) obstruction is a rare but potentially fatal complication of acute anterior wall infarction. We present a patient with an acute coronary syndrome (ACS) with ST-segment elevation in the anterior leads, transient TTS and transient LVOT obstruction with systolic anterior motion (SAM) of the mitral valve and severe mitral regurgitation. This is the first report of myocardial bridging associated with TTS, and the first report of TTS associated with dynamic LVOT obstruction with SAM and mitral regurgitation.

Randomized study comparing cardiac response in endovascular and open abdominal aortic aneurysm repair.

BACKGROUND: The aim was to compare the cardiac response and the incidence of adverse cardiac events during and after endovascular (EVAR) and open (OR) repair of abdominal aortic aneurysms (AAAs). METHODS: Seventy-six patients with an AAA suitable for EVAR, and in a general condition allowing open surgery were randomized to EVAR (57 patients) or OR (19 patients). The analysis was on an intention-to-treat basis. Haemodynamic variables were assessed intraoperatively before, during and after aortic occlusion. During the procedure myocardial ischaemia was identified with use of electrocardiography (ECG) and transoesophageal echocardiography (TEE). After operation, cardiac complications were diagnosed by clinical observation, 12-lead ECG at 1 h, 1 day and 7 days, echocardiography at 1 month and measurement of cardiac enzymes. RESULTS: After aortic occlusion, a greater decrease in systemic vascular resistance compared with baseline was observed with OR than with EVAR (- 396 and - 70 dyne s/cm5 respectively; P = 0.03). The stroke work index, as a direct measure of myocardial performance, demonstrated a decrease during OR and an increase during EVAR during aortic occlusion (- 6.6 and + 1.7 g m/m2 respectively; P = 0.03) as well as after aortic occlusion (- 7.6 and + 3.4 g m/m2 respectively; P < 0.01), compared with baseline. The incidence of postoperative clinical cardiac complications was comparable in the two study groups; however, myocardial ischaemia, as observed by ECG and TEE, was observed more frequently in the OR group (ten of 19 versus 15 of 57 patients; P = 0.05). CONCLUSION: Haemodynamic changes were less severe and there was a lower incidence of myocardial ischaemia during EVAR than during OR. Studies are needed to demonstrate whether this may reduce the operative mortality rate.

Cardiac response and complications during endovascular repair of abdominal aortic aneurysms: a concurrent comparison with open surgery.

PURPOSE: The purpose of this study was to assess and to compare perioperative changes in left ventricular function and the incidence of adverse cardiac events in two groups of patients with abdominal aortic aneurysms, one during endovascular aneurysm repair (EAR) and the other during open aneurysm repair (OAR). METHODS: One hundred twenty consecutive patients who underwent EAR (49 patients) or OAR (71 patients) were prospectively studied. During the operation, the left ventricular function was assessed by the recording of the left ventricle stroke work index (SWI) and the cardiac index (CI) with a pulmonary artery catheter. Measurements were performed before, during, and after stent-graft deployment or aortic cross-clamping. Both maneuvers were defined as aortic occlusion (AO). Transesophageal echocardiography was performed to identify signs of wall motion abnormalities of the left ventricular wall, which indicated myocardial ischemia. Six-lead electrocardiograph monitoring was maintained until discharge from the intensive care unit. Postoperative cardiac complications were diagnosed by clinical observation, 12-lead ECG analysis at 1, 3, and 7 days after the operation, transthoracic echocardiography at 1 month, and measurement of cardiac enzymes. RESULTS: The two study groups were comparable with regard to most clinical aspects. The baseline myocardial performance was worse in patients who underwent EAR compared with patients who underwent OAR, as indicated by a reduced SWI (33.1 and 37.4, respectively; P =.03). During AO there was a comparable increase of the CI in both groups. However, after AO the rise in CI was higher in patients who underwent OAR compared with patients who underwent EAR (0.7 and 0.2, respectively; P <.01), representing a more pronounced hyperdynamic state. In addition, the SWI demonstrated a decrease in patients who underwent OAR compared with an increase in patients who underwent EAR during AO (-1.4 and +1.9, respectively; P =.04) and after AO (-0.9 and +2.6, respectively; P =.01). These findings represent more severe myocardial stress in patients who underwent OAR. The incidence of postoperative clinical cardiac adverse events was comparable in the two study groups. However, myocardial ischemia, as indicated by electrocardiography and transesophageal echocardiography, had a higher incidence in patients who underwent open surgery as compared with patients whose condition was managed endovascularly (57% and 33%, respectively; P =.01). CONCLUSION: Hemodynamic alterations during endovascular repair were not as severe as those in patients with open surgery and indicated less myocardial stress in the former category. These findings may explain a lower incidence of myocardial ischemia that was observed during endovascular repair. A lower frequency of clinical perioperative cardiac events in patients undergoing endovascular treatment may ultimately be expected.

Hemodynamics of the Freestyle bioprosthesis in young patients.

The objective of this study was to analyze hemodynamics of the Freestyle stentless bioprosthesis in young patients compared with the older age group. The Freestyle aortic bioprosthesis is a stentless aortic xenograft. Hemodynamics are proven to be good in older patients for a long period. Experience is limited in the younger age group. Therefore the hemodynamics of 71 patients younger than 60 years (14-59 years) were compared with the data of 471 patients older than 60 years (60-86 years) during a follow-up period of 6 years. In the study, 542 consecutive patients with a Freestyle aortic bioprosthesis underwent an echocardiographic and Doppler examination according to a common protocol. Investigations were done within 4 weeks after operation, after 3 to 6 months, and then every year. Mean gradients of the young patients were 8.7 +/- 5.3 mm Hg at discharge and remained between 5.2 +/- 3.9 mm Hg and 11 +/- 5.6 mm Hg during the complete follow-up period. Gradients of the older patients were 8.3 +/- 5.4 mm Hg at discharge and remained between 5.1 +/- 3.7 mm Hg and 6.5 +/- 7.9 mm Hg. Cardiac index during the follow-up period was equal in both groups. Doppler values were evaluated for the Freestyle stentless porcine bioprostheses in the aortic root both for patients younger than 60 years and patients over 60 years of age. Midterm hemodynamic performance is equal in both groups.

Echocardiographic parameters of the freestyle stentless bioprosthesis in aortic position: the European experience.

The objective of this study was to determine normal Doppler and 2-dimensional characteristics of the Freestyle stentless aortic bioprosthesis. The Freestyle aortic bioprosthesis is a new type of aortic xenograft, and experience is limited. We therefore determined the normal range of echocardiographic and Doppler examinations of this valve. Three hundred thirty-nine consecutive patients with a Freestyle aortic bioprosthesis underwent an echocardiographic and Doppler examination according to a common protocol. Investigations were done within 4 weeks after operation, after 3 to 6 months, and after 1, 2, and 3 years. With a valve size from 19 to 27 mm, mean gradients decreased from 7.9 +/- 5.1 mm Hg at discharge to 5.5 +/- 3. 8 mm Hg after 3 to 6 months (P <.001). Thereafter, gradients remained stable. Effective orifice area 1 year after implantation was 1.59 +/- 0.58 cm(2) for the 21-mm valves, 1.92 +/- 0.74 cm(2) for the 23-mm valves, 2.03 +/- 0.64 cm(2) for the 25-mm valves, and 2.52 +/- 0.72 cm(2) for the 27-mm valves (P <.001). The performance index, the ratio of the measured effective orifice area in the patient divided by the effective orifice area measured in vitro, increased from 67% +/- 20% at discharge to 82% +/- 29% after 1, 2, and 3 years. Performance index was especially very high in the smaller-sized valves. After implantation with the subcoronary technique or root-inclusion technique, small cavities could be seen between the native aortic root and the Freestyle valve. Doppler values were evaluated for the Freestyle stentless porcine bioprostheses in the aortic root. Gradients appear to be close to those measured in native valves over a time period of 3 years.

Influence of changes in ionized calcium on cardiovascular reactivity during hemodialysis.

In order to prevent hypercalcemia due to the treatment of secondary hyperparathyroidism the use of low calcium dialysate is advocated. However, as calcium ions play a pivotal role in both myocardial and vascular smooth muscle contraction, lowering the dialysate calcium concentration might result in a further impairment of the cardiovascular response during dialysis. Therefore, arterial blood pressure, forearm vascular resistance (FVR) and venous tone (VT) (straing-gauge plethysmography) as well as cardiac dimensions and output (echocardiography) were measured in 10 hemodynamically stable dialysis patients (ejection fraction > 30%) during two standardized sessions of three-hour combined ultrafiltration-hemodialysis (UF + HD) at two different dialysate calcium concentrations: 1.25 and 1.75 mmol/l. High calcium UF + HD resulted in a significant increase in plasma ionized calcium (+0.19 +/- 0.11 mmol/l; p < 0.01) while ionized calcium remained unchanged during low calcium UF + HD (-0.02 +/- 0.07 mmol/l). As a result, systolic, diastolic and mean arterial blood pressure were respectively 14 +/- 10, 5 +/- 7 and 9 +/- 9 mmHg higher during high calcium UF + HD as compared to low calcium UF +/- HD (p < 0.05). There were no significant differences in FVR and VT between the two treatments. During both treatments FVR increased while VT decreased. In addition, there were no differences in calculated systemic vascular resistance. However, with comparable end-diastolic dimensions, stroke volume (-18 +/- 13 ml) and cardiac output (-1.3 +/- 1.5 l/min) decreased significantly (p < 0.05) only during low calcium UF + HD. We conclude that even in hemodynamically stable patients changes in plasma ionized calcium are an important determinant of the blood pressure response during dialysis therapy. Whereas peripheral vascular reactivity is unaffected by changes in ionized calcium, myocardial contractility is improved with higher dialysate calcium concentrations.

Prediction of surgical strategy in mitral valve regurgitation based on echocardiography. Interuniversity Cardiology Institute of The Netherlands.

The purpose of this prospective multicenter study of 350 consecutive patients who were accepted for mitral valve surgery because of severe regurgitation, was to assess the value of preoperative transthoracic and transesophageal echocardiography in predicting the surgical strategy in severe mitral regurgitation: repair or replacement. The cardiologist predicted the surgical strategy on the basis of the echocardiographic examination, according to predefined guidelines for repair and replacement. The predicted strategy and motivation thereof were compared with the surgical findings and procedure that was performed. Agreement on the basis of transthoracic echocardiography was reached in 86% of the repair patients and on the basis of transesophageal echocardiography in 89%. Agreement on the basis of transthoracic echocardiography was reached in 74% of the replacement patients and on the basis of transesophageal echocardiography in 75%. This study underlines the potential role of echocardiography in predicting the surgical procedure to be applied, provided that both surgeon and cardiologist use the same nomenclature and that the guidelines for replacement/repair are adhered to. Both transthoracic and transesophageal echocardiography appear to be equally accurate in predicting the optimal surgical procedure in this respect.

Comparison of transthoracic and transesophageal echocardiography with surgical findings in mitral regurgitation. The ESMIR Research Group.

This prospective study was conducted to ascertain whether echocardiographic evaluation could provide more insight into the genesis of mitral regurgitation (MR) before surgery. All patients underwent preoperative transthoracic and transesophageal echocardiography. Nine centers participated in the ESMIR (Echocardiographic Selection of patients for MItral valve Reconstruction) study and 350 patients were included. Compared with surgical findings, the percentage of functional abnormalities correctly predicted by both echo modalities was highest in patients with increased leaflet mobility (83% for transthoracic and 86% transesophageal echocardiography). In contrast, in normal leaflet mobility, the prediction was better by transthoracic than by transesophageal echocardiography (75% vs 64%). In patients with restricted leaflet mobility, the predictive value of both techniques was similar. The diagnostic yield of anatomic abnormalities of both echo techniques was similar, except for chordal rupture; a sensitivity by transesophageal echocardiography of 79% and by transthoracic echocardiography of 57% (p < 0.001). In general, the sensitivity of each echo technique for detecting anatomic abnormalities was <70%, except for annular dilatation, leaflet thickening, and chordal rupture. At surgery, the prevailing functional condition was increased leaflet mobility (42%). The conclusion is that both echo techniques provide adequate information regarding the functional condition of the mitral valve apparatus, not withstanding limitations in assessing anatomic details. Transthoracic echocardiography appears to be sufficient for preoperative evaluation of MR.

Acute intervention with captopril during thrombolysis in patients with first anterior myocardial infarction. Results from the Captopril and Thrombolysis Study (CATS).

The study was designed to examine the safety and efficacy of acute interventional use of captopril on left ventricular volumes, ventricular arrhythmias and neurohormones during thrombolysis in patients with a first anterior myocardial infarction, within 6 h of onset of symptoms. Left ventricular dysfunction and prognosis after myocardial infarction can be improved by angiotensin converting enzyme inhibition started after the ischaemic phase. Experimental evidence suggests that intervention during thrombolysis may lead to even further benefit. In a randomized, double-blind placebo-controlled trial, 298 patients with a first anterior myocardial infarction, eligible for thrombolytic therapy were treated with captopril 6.25 mg or placebo, started immediately upon streptokinase infusion and titrated to 25 mg t.i.d.. The efficacy of captopril by an intention-to-treat-analysis to reduce left ventricular volumes, ventricular arrhythmias, neurohumoral activation and enzymatic infarct size was measured. During dose titration, mean blood pressure and heart rate were similar in both groups. However, hypotension after the first dose was reported in 18 patients on placebo and 31 patients on captopril (P < 0.05). At discharge, 80% of patients were on study medication. Left ventricular volumes were significantly increased in both groups at 3 months, but they tended to be lower in the captopril group; however, the differences were not statistically significant. The incidence of accelerated idioventricular rhythm and non-sustained ventricular tachycardia in captopril patients was lower than in placebo patients (P < 0.05), parallelled by transiently lower norepinephrine levels (P < 0.05) upon thrombolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of two-dimensional echocardiography for immediate detection of myocardial ischemia in the emergency room.

Inappropriate discharge from the emergency room of patients with acute chest pain may have serious consequences. Regional asynergy is one of the first signs of myocardial ischemia and can be detected with 2-dimensional echocardiography (2-DE). This study determines the value of 2-DE in the emergency room for immediate detection of myocardial ischemia causing acute chest pain at the time the electrocardiogram was nondiagnostic. Forty-three patients (32 men and 11 women) with a normal or nondiagnostic electrocardiogram during acute chest pain were studied with 2-DE. Only patients without a previous myocardial infarction and without known coronary artery disease (CAD) were studied. The entire left ventricular wall was examined for presence of regional asynergy. Coronary angiography was performed within 3 weeks. Cardiac enzyme levels were measured serially to establish or rule out an acute myocardial infarction. Sensitivity of 2-DE for detection of myocardial ischemia was 88% (22 of 25), specificity 78% (14 of 18), negative predictive accuracy 82% (14 of 17) and positive predictive accuracy 85% (22 of 26). Sensitivity of 2-DE for detection of acute myocardial infarction was 92% (12 of 13), specificity 53% (16 of 30) and negative predictive accuracy 94% (16 of 17). Thus, 2-DE during pain and a nondiagnostic electrocardiogram can readily identify patients with CAD in the emergency room, and it can accurately rule out an acute myocardial infarction.

Left ventricular thrombus incidence and behavior studied by serial two-dimensional echocardiography in acute anterior myocardial infarction: left ventricular wall motion, systemic embolism and oral anticoagulation.

Serial two-dimensional echocardiography was performed to detect left ventricular thrombus in 92 consecutive patients with a confirmed first acute anterior myocardial infarction. Thirty left ventricular thrombi were diagnosed in these 92 patients. The cumulative percent of identified thrombus in each echocardiographic examination in the surviving patients was 27% at less than 24 h; 57% at 48 to 72 h; 75% at 1 week and 96% at 2 weeks. The thrombus shape was defined as mural in 53% and protruding in 47% of patients. Systemic embolism (stroke) was noted during hospitalization in two patients with a protruding thrombus. At 12 weeks of follow-up, patients with thrombus had poorer (and almost unchanged from baseline) global left ventricular function as expressed by wall motion score compared with that of patients without thrombus, who exhibited significant improvement. Global left ventricular wall motion in patients with persisting or resolved thrombus was similar during follow-up. Apical wall motion worsened in 70% of the patients with persisting thrombus and in 25% of the patients with resolved thrombus (p less than 0.1). In the 22 surviving patients with thrombus, resolution or change in thrombus shape or size was noted in 14 of the 15 patients receiving anticoagulant therapy and in 4 of the 7 untreated patients. Six of the 18 patients with an early- (48 to 72 h) and none of the 12 patients with a later-formed thrombus died. Maximal serum enzyme levels, percent with Killip functional class III to IV and left ventricular wall motion score were higher in the patients with an early- than in those with a later-formed thrombus.(ABSTRACT TRUNCATED AT 250 WORDS)

Emergency room infusion of intravenous streptokinase in acute myocardial infarction: feasibility, safety, and hemodynamic consequences.

Between September 1, 1986, and December 31, 1987, sixty-four consecutive patients younger than 70 years, with early (less than 4 hours) symptoms and signs of myocardial infarction, were treated with 1.5 million units streptokinase intravenously in the emergency room (ER group) before admission to the coronary care unit. Data from these patients were compared in retrospect to those of 66 consecutive patients with myocardial infarction who were treated with intravenous streptokinase in the coronary care unit (CCU group) before September 1, 1986. Time between first symptoms and initiation of fibrinolytic therapy was significantly shorter in the ER group: 114 +/- 53 minutes vs 150 +/- 56 minutes in the CCU group (p less than 0.001). The incidence of in-hospital complications was similar in both groups. However, left ventricular stroke work index during the stay in the coronary care unit was 50 +/- 19 gm/m2 in the ER group vs 42 +/- 14 in the CCU group (p = 0.02). Also the echocardiographic left ventricular wall motion score at 48 hours after admission tended to be better in the ER group: 6.7 +/- 4.0 compared to that in the CCU group (7.6 +/- 4.5; p = 0.29). In conclusion, infusion of intravenous streptokinase in the emergency room is feasible and safe and results in a significant time gain leading to a better hemodynamic profile. Within the hospital the emergency room is the ideal place for intravenous fibrinolytic therapy in eligible patients with acute myocardial infarction.

Effect of low dose acetylsalicylic acid on the frequency and hematologic activity of left ventricular thrombus in anterior wall acute myocardial infarction.

In this prospective, randomized, placebo-controlled trial the effect of 100 mg acetylsalicylic acid (ASA) once daily on the incidence, hematologic activity and embolic potential of left ventricular (LV) thrombosis was studied in 100 consecutive patients with a first anterior wall acute myocardial infarction (AMI). Patients were randomized to ASA or placebo less than 12 hours after onset of symptoms. Heparin, 5,000 IU subcutaneously twice daily, was given to all patients during immobilization. Echocardiography was performed less than 24 hours, 48 to 72 hours and 1, 2, and 12 weeks after AMI. LV thrombosis was detected by echocardiography in 30 (33%) of the 92 evaluable patients (15 patients given ASA and 15 given placebo). Indium-111 platelet scintigraphy was done in 17 of the 22 patients with an LV thrombus at the second week echocardiogram. Among 7 ASA-treated patients, 4 had positive images; among 10 placebo patients, 5 had positive images. LV thrombus resolution was noted in 3 of 9 patients with a positive scan and in 5 of 8 patients with a negative platelet scan. In 7 of 10 ASA-treated patients and 5 of 12 placebo-treated patients thrombus resolution was observed (difference not significant). Systemic embolism occurred in 2 patients, both given ASA, during the first week after AMI. Thus, low dose ASA has no effect on the incidence, hematologic activity and embolic potential of LV thrombosis in anterior wall AMI.