Cardiac Catheterization

A cardiac catheterization may be done to perform various tests, including

The cardiac catheterization is accomplished by inserting a catheter via peripheral arteries or veins into the cardiac chambers, the pulmonary artery and the coronary arteries and veins. A cardiac catheterization may be done to perform various tests including angiography Intravascular ultrasonography measurement of cardiac output (CO) detection and quantification of shunts endomyocardial biopsy measurements of myocardial metabolism These tests determine the coronary anatomy, heart anatomy, heart function and pulmonary and arterial hemodynamics, a diagnosis ask questions and find appropriate treatment. The cardiac catheter is also a basis for a number of therapeutic intervention (see percutaneous coronary intervention) Procedure Patients must remain sober 4-6 h prior to the cardiac catheterization. Most patients do not require hospitalization overnight, unless there is a therapeutic procedure performed. Left heart catheterization Left heart catheterization is most commonly used to assess cardiac anatomy left heart catheterization is also used to include to evaluate Aortic blood pressure Systemic Vascular Resistance Aortenklappenfunktion mitral valve Left ventricular pressure and function The investigation is over, the puncture of the femoral artery, the subclavian artery the radial artery or the brachial artery performed, and a catheter is inserted into the coronary ostia or through the aortic valve into the left ventricle. The catheterization of the left atrium (LA) and left ventricle (LV) is sometimes a transseptal puncture during right heart catheterization durchgeführt.Rechtsherzkatheter right heart catheter is most commonly used to assess the following, right atrial (RA) pressure Right Ventricular (RV) pressure pulmonary artery pressure pulmonary arterial wedge pressure (PAOP- diagram of the cardiac cycle, with pressure curves of the heart chambers, cardiac murmurs, Jugularvenenpulswelle and ECG.): PAOP corresponds approximately to the left atrial and left ventricular end-diastolic pressure. In critically ill patients PCWP is used to determine the volume status and can help with simultaneous measurement of cardiac output to control the treatment. The right coronary catheter is also useful for the assessment of pulmonary vascular resistance, pulmonary or tricuspid function intracardiac shunts and right ventricular pressure. The measurements of right heart catheter can help in the diagnosis of cardiomyopathy, constrictive pericarditis and cardiac tamponade when noninvasive tests are not diagnostic. And they are an essential part of the assessment of a heart transplant or mechanical cardiac support (z. B. Use of a ventricular assist device) The process is carried out through the puncture of the femoral vein, subclavian vein, the internal jugular vein or via a cubital vein. A catheter is inserted through the tricuspid valve in the RA, in the RV and through the pulmonary valve into the pulmonary artery. A selective catheterization of the coronary sinus is also possible. Diagram of the cardiac cycle, with pressure curves of the heart chambers, cardiac murmurs, Jugularvenenpulswelle and ECG. The phases of the cardiac cycle, the atrial systole (a), the isometric contraction (b), the maximum ejection phase (c), the phase of the ejection reduction (d), the protodiastolische phase (e) that isometric relaxation (f), the phase of the rapid influx (g), the diastase or phase of slow LV filling (h). For better presentation, the time intervals between the flaps events have been modified and the Z-point extended. AO = Opening of the aortic valve; AC = closure of the aortic valve; LV = Left ventricle; LA = left atrium; RV = right ventricle; RA = right atrium; MO = opening of the mitral valve. Specific tests during cardiac catheterization angiography Injection of X-ray contrast media into the coronary arteries or the pulmonary arteries, the aorta and the ventricles is useful under certain conditions. The digital subtraction angiography (DSA) is used for non-moving arteries and for the Cineangiographie. Coronary angiography via cardiac catheterization is used to represent the Koronararterienanatomie in various clinical situations, such. As in patients with suspected coronary atherosclerotic or congenital disease, valve disease before valve replacement and unexplained heart failure. A Pulmonalangiographie over the right heart catheter can be used to diagnose a pulmonary embolism. Intraluminalfüllungsdefekte or arterial terminations are diagnostic. A radioactive contrast agent is normally selectively injected into one or both of the pulmonary arteries and their segments. However, the Computed Pulmonalangiographie (CTPA) has replaced the right heart catheterization for the diagnosis of pulmonary embolism largely. Angiography of the aorta via the left ventricular catheter is used to represent the aortic valve, a coarctation, a patent ductus arteriosus and dissection. The ventriculography is used to represent the left ventricular wall motion, and the left ventricular outflow tract, wherein subvalvular, valvular and supravalvular regions are included. It is also used to assess the severity of mitral regurgitation and to determine their pathophysiology. After left ventricular mass and volume have been determined in a monoplane or biplane LV angiogram, can end-systolic and end-diastolic volume and ejection fraction calculated werden.Intravasculärer ultrasound Miniaturized ultrasound heads at the end of coronary catheters can deliver pictures of the vessel lumen and the vessel wall and determine the blood flow. This technique is increasingly simultaneously Optical with coronary angiography durchgeführt.Optische coherence tomography coherence tomography (OCT) is an optical analog of intracoronary ultrasound imaging, which measures the amplitude of the backscattered light to determine the temperature of coronary plaques, and can help determine whether lesions with high risk of future ruptures are present (leading to acute coronary syndrome) .Tests for cardiac shunts the measurement of the acid substances maintenance at successive points in the heart and the great vessels can determine the presence, the direction and volume of central shunts. The maximum normal oxygen content difference between the structures is as follows: The pulmonary artery and the right ventricle: 0.5 ml / dl The right ventricle and right atrium: 0.9 ml / dl The right atrium and the superior vena cava: 1.9 ml / dl When the oxygen content in a heart chamber exceeds the value of the ventricle located proximal, a left-to-right shunt is probably at this level. Right-to-left shunts are very suspicious if the LA, LV or arterial oxygen saturation is low (?92%) and not improved in pure Sauerstoffabe (fractional inspiratory l O2 = 1.0). Left ventricular and arterial oxygen desaturation and additionally increased oxygen content in blood samples that are obtained below the shunt on the right side of the circulation, speak for a bidirectional Shunt.Messung cardiac output and the flow measurement The cardiac output (CO) is ejected from the heart per minute blood volume (Normal values: 4-8 l / min). The techniques used are CO to be calculated. Fick technique cardiac output indicator dilution technique thermodilution technique (see Table: cardiac output equations) cardiac output equations Fick technique counter is absorbed through the lungs O2 (ml / min). Indicator dilution technique denominator is the sum of the concentrations of dye (C) is (t) at each time interval. Thermodilution TB – TI is the difference between body and Injektattemperaturen; is injectate usually dextrose or saline. Denominator is the sum of the temperature changes in each time interval (t). SaO2 = arterial O2 saturation (%); SvO2 = mixed venous O2 saturation (%) measured in the pulmonary artery. Clinical calculator: cardiac output “Multicalc” clinical calculator: cardiac output (Cardiac Output) The Fick technique cardiac output is proportional to oxygen consumption divided by the arteriovenous oxygen difference. Dilution techniques are based on the assumption that a current injected into the bloodstream indicator appears proportional to the cardiac output and disappears. Typically, the cardiac output is in proportion to body surface area (BSA) as a cardiac index (CI, cardiac index) in l / min / m2 (i.e., CI = CO / BSA; see Table:.. Standard values ??of the cardiac index and related measurements) indicated. The BSA is calculated by the DuBois body length-weight equation: Clinical calculator: body surface area (Du Bois method) standard values ??of the cardiac index and related measurements measurement standard value SD oxygen uptake 143 ml / min / m2 * 14.3 Arteriovenous oxygen difference 4.1 dl 0.6 Cardiac index 3.5 l / min / m2 0.7 Stroke Volume Index 46 ml / beat / m2 8.1 Totaler systemic resistance 1130 dynes-sec-cm-5 178 Totaler lung resistance 205 dynes-sec-cm-5 51 pulmonary arteriolarer resistor 67 dynes-sec-cm-5 23 * Varies with body mass index. SD = standard deviation. Adapted from Barratt-Boyes BG, Wood EH: Cardiac output and related measurements and pressure values ??in the right heart and associated vessels, together with analysis of of the hemodynamic response to the inhalation of high oxygen Mixtures in healthy subjects. Journal of Laboratory and Clinical Medicine 51: 72-90, 1958. An endomyocardial biopsy endomykardiale biopsy helps determine the transplant rejection and cardiac muscle diseases caused by infections or Infiltraterkrankungen. The biopsy catheter (bioptome) can be inserted into each of the two chambers of the heart, usually in the right ventricle. 3-5 myocardial samples are taken from the septal endocardium. The main complication of endomyocardial biopsy, which ,, cardiac perforation occurs in 0.3-0.5% of patients and can cause haemopericardium that can lead to cardiac tamponade. A violation of the tricuspid valve and the supporting chordae can also occur and tricuspid regurgitation führen.Messungen coronary artery flow Coronary angiography shows the presence and degree of stenosis, but not the functional significance of the lesion (ie, how much blood flows through the stenosis) or, whether it is probable that a specific lesion caused symptoms. Extremely thin lead wires with pressure sensors or Doppler sensors are available. The data from these sensors can be used to estimate the blood flow of the coronary arteries, the part flow reserve (FFR) is expressed. FFR is the ratio of maximum flow through the stenotic area of ??the normal maximum flow. A FFR of <0.75 to 0.8 is considered abnormal. This flow estimates correlate well with the intervention necessity and the long-term result. Lesions with FFR> 0.8 do not seem to benefit from stenting. This flow measurements are best suited for moderate lesions (40-70% stenosis) and multiple lesions (to identify those who are clinically significant). Contraindications cardiac catheterization Among the relative contraindications cardiac catheterization include renal insufficiency coagulopathy fever Systemic infection Uncontrolled arrhythmia or hypertension Uncompensated heart failure contrast agent allergies in patients who do not receive adequate premedication complications of cardiac catheterization The incidence of complications after cardiac catheterization ranges from 0.8 to 8% depending on patient factors, technical factors and the experience of the operator. To the patient factors that increase the risk of complications, including heart failure With age, valvular heart disease Peripheral arterial disease COPD Chronic kidney disease insulin-dependent diabetes Most complications are minor and can be treated easily. Serious complications (eg. As cardiac arrest, anaphylactic reactions, shock, convulsions, cyanosis, nephrotoxicity) are rare. The mortality rate is 0.1-0.2%. MIyokardinfarkt (0.1%) and stroke (0.1%) can lead to significant morbidity. The incidence of stroke is higher in patients> 80 years. Generally involve complications, the contrast agent effects of the catheter The access site complications contrast, the injection of contrast agent causes a temporary feeling of warmth in the body in many patients. Tachycardia, a slight decrease in systemic blood pressure, an increase in cardiac output, nausea, vomiting and coughing may occur. Rarely enters a bradycardia when large amounts of contrast media are administered. coughing with the demand of normal sinus rhythm is often reached again. More serious reactions (see also X-ray contrast media and contrast media reactions) Allergic reactions include contrast agents Kontrastmittelnephropathie Allergic reactions can be urticaria and conjunctivitis, usually on diphenhydramine 50 mg i.v. speak to. Anaphlylaxie with bronchospasm, laryngeal edema, and dyspnea are rare reactions. They are with inhaled salbutamol or epinephrine 0.3-0.4 ml s.c. treated. Anaphylactic shock is treated with epinephrine and other supportive measures. Patients with previous allergic reactions to contrast agents may be premedicated with prednisone (50 mg p.o. 13 h, 7 h and 1 h prior to injection of the contrast agent) and diphenhydramine (p.o. or 50 mg i.m. 1 hour before the injection) was obtained. If patients need immediate imaging, should diphenhydramine 50 mg po them or iv 1 hour before the injection of contrast agent and hydrocortisone 200 mg i.v. every 4 hours will be given until the imaging is complete. A contrast nephropathy is defined as impairment of renal function (either a 25% increase in serum creatinine with respect to the basic value, or an increase of 0.5 mg / dl of the absolute value) within 48 to 72 h i.v. Administration of the contrast agent. In patients at risk, the use of low-osmolarem or iso-osmolar contrast and saline infusion reduced i.v. for 4 to 6 hours prior to angiography and 6 to 12 h after this risk. In such patients to assess serum creatinine 48 h after injection of Kontrastmittels.Katheterassoziierte complications if the catheter tip touches the Ventrikelendokard, often rare ventricular arrhythmia, ventricular fibrillation but on. If it occurs, immediately defibrillated (DC) conversion is prescribed. The disruption of an atherosclerotic plaque through the catheter can trigger a Atheroembolie. Emboli from the aorta can lead to stroke or nephropathy. Embolism of the coronary arteries can cause a heart attack. Coronary Herzdissektion möglich.Komplikationen the access side to the vascular complications include bleeding hematoma pseudoaneurysm, arteriovenous (AV) fistula limb ischemia may experience bleeding from the access site and brought to a halt usually with compression Light bruises and small haematomas are common and do not require specific investigation or treatment. A large or enlarging lump should be examined with ultrasound to distinguish a hematoma from a pseudoaneurysm. A “bruit” on the site (with or without pain) indicates an AV fistula, which can be diagnosed with ultrasound. Hematoma dissolve usually with time and require no specific therapy. Pseudoaneurysms and AV fistulas dissolve usually with compression; those who persist may require surgical repair. An access via the radial artery is more pleasant in general for the patient and carries a much lower risk of hematoma or pseudoaneurysm or arteriovenous fistula compared with the access via the femoral artery. For more information ACR Manual on Contrast Media 2012 American College of Cardiology Foundation / Society for Cardiovascular Angiography and Interventions Expert Consensus Document on Cardiac Catheterization Laboratory Standards Update

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