Healthcare

 Retrieve Password
 join us
search

Sinoatrial block

Read in CN

   

[Intro]

Overview: sinoatrial block (sinoatrial block, SAB) referred to as sinus room block. Department of sinus tissue around the lesion, the excitement spread to reach the sinus node atrial issued to extend the time or can not be spread, leading to atrial ventricular asystole.

[Cause]

sinoatrial block is what causes it?

(a) causes

1. mostly seen in patients with structural heart disease is the most common cause of coronary heart disease, about 40%, around the sinus node due to myocardial ischemia lead to organic damage. Posterior wall acute myocardial infarction, the incidence of sinoatrial block of 3.5%, compared with sinus bradycardia is much less, its causes can be secondary to increased vagal tone, in addition to the sinus node ischemia or infarction also common. In addition, also found in hypertensive heart disease, rheumatic heart disease, cardiomyopathy, congenital heart disease, chronic inflammation or ischemia-induced sinus node and surrounding tissue lesions.

2. hyperkalemia, hypercapnia, diphtheria and influenza.

3. sinoatrial peripheral zone of degenerative sclerosis, fibrosis, fat-based or amyloidosis.

4. drugs (such as digitalis, quinidine, verapamil, disopyramide, amiodarone, β-blockers, etc.) poisoning and high doses of propafenone may cause, but mostly temporary.

5. can be seen in increased vagal tone or the health of carotid sinus hypersensitivity who atropine trials.

6. a few reasons unknown, the individual may be familial.

7. rare due to intravenous injection of magnesium sulfate (for injection can not be excluded due to too fast), hypokalemia (<2.6mmol / L = may also be occurred.

8. few can simultaneously atrioventricular block, was progressively increased, said two-junction syndrome.

(B) the pathogenesis

issued excited because the sinus node potential is very small, on the surface ecg tracings not only with the sinus node electrogram can be recorded, excited to be issued by the SA node sinoatrial transition zone to the surrounding atrial muscle, the resulting atrial atrial depolarization wave that sinus P wave, as a way to indirectly measure the sinus node activity. sinuses room block and sinus arrest is different from the sinus node is still on time, regularly issued excitement, but excitement from the sinoatrial transition zone outward spread of atrial muscle, the occurrence of conduction delay or not heard, for the spread of resistance stagnation of the former and the second was the performance of type Ⅰ sinoatrial block, which manifests second typesinoatrial block or third degree sinoatrial block.

[Sign]

sinoatrial block early symptoms?

sinoatrial block may be temporary, but also sustainable presence or repeated attacks. sinoatrial block in patients often asymptomatic, may also have mild heart palpitations, fatigue and a sense of "leakage jump" cardiac auscultation can be found in arrhythmia, bradycardia, "leakage Jump" (long interval). If repeated or prolonged episodes of block, continuous cardiac missed jump occurs, and there is no escape, can be dizziness, syncope, coma, - Adams syndrome. In addition, there are clinical manifestations of primary disease.

sinoatrial block was manifested as sinoatrial conduction time, difficult to diagnose on the surface ECG; second degree sinoatrial block based on history, symptoms and ecg can be diagnosed; third-degree sinoatrial block showed sinus P wave disappeared, and sinus arrest difficult to distinguish.

[Aftertreat]

sinoatrial block ate?

dietary considerations: eating light, less meat and more factors, tobacco and alcohol, and other non-specific contraindications.

diet: pain herbal tea to take safflower 15 g, chuanxiong 12 g, red peony 10 grams, down incense 10 grams, 30 grams of Salvia, add boiling water to the residue after juice , taken on behalf of a tea concoction, served a day. blood circulation, qi analgesic efficacy, exacerbation of angina pectoris for patients to drink.

safflower saffron honey to take 150 grams of chuanxiong 150 grams. Add boiling water to the residue left after the juice, pour the concoction pot, low heat and boiled gravy, add honey and mix thoroughly after cooling to take. 3 times a day, each 10 ml, can be served 30 days. Suitable for angina pectoris pain has eased, but there are chest tightness, suffocation, dark purple tongue and other performers take stagnation of qi and blood stasis.

red porridge heterophylla 50 participants grams, 10 grams of safflower. The two herbs add boiling water, leave residue juice, add the washed rice concoction 30 grams of green beans 20 grams, boiled gruel taking 1 day, 10 days for a course. Suitable for recovery of coronary heart disease deficiency fatigue, chest tightness, heart palpitations, blood stasis performers take.

[Prevent]

sinoatrial block should be how to prevent?

prognosis strengthening exercises

sinoatrial block, such as those for the occasional multi-functional system increased vagal tone, etc. cause, or frequent episodes of long-lasting and more for organic due. ventricular rate greater than 50 times / min, short duration, no fainting, no - adams syndrome made by the general prognosis is good. Such as the elderly or in patients with advanced heart disease, frequent or persistent sinoatrial block, if no escape rhythm may occur - Adams syndrome, the prognosis is poor.

[Treat]

sinoatrial block precautions before treatment?

sinoatrial block the majority of asymptomatic, heart rate too slow can cause significant fatigue, dizziness, chest tightness, and so on. Can cause severe cardiogenic syncope. Light without treatment. stubborn and persistent, and cardiogenic syncope or fainting hair of required placement of artificial cardiac pacemaker.

precautions:

1. timely and aggressive treatment of primary disease control, elimination of primary disease prevention Benbingfasheng the key.

2. the rational use of digitalis preparations, quinidine and other antiarrhythmic drugs.

3. living there often, eating right, to feel comfortable, proper physical exercise, to make tendons and blood circulation.

sinoatrial block Chinese medicine treatment methods

take epimedium and astragalus, Codonopsis, aconite, Asarum, with the use of ephedrine, boiling, can cure sick sinus syndrome and atrioventricular block.

tcm syndrome treatment:

(1) Acute heat type:

syndrome: incidence of this type are mostly within 6 months, accompanied by fever, sore throat and respiratory symptoms, and there are heart palpitations, chest pain, easy red urine, pulse number or statement on behalf of illness, moss yellow, red tongue.

rule: heat purging fire, yin and yang Xin.

Recipe: The Yinqiaosan, flavors disinfect drinking, Xie Xin Tang, bamboo soup gypsum addition and subtraction. medicinal honeysuckle, forsythia, skullcap, dandelion, Anemarrhena, Folium, Radix, Yuan ginseng, licorice.

(2) Heart yin loss type:

syndrome: more for recovery, the course in 6 months or more than one year. Zheng Jian palpitations, shortness of breath, chest oppressed, upset, dry mouth, dysphoria hot or often fever, rapid pulse or intermittent, red tongue, no moss or less moss.

rule is: clearing away heat, and to soothe the nerves.

Recipe: Yiguangjian, Suanzaorentang, Bu Xin dan and subtraction. medicinal habitat, Radix, Radix, Yuan ginseng, lotus, fried Zao Ren, dandelion,

fu Shen. amber powder (red) Schisandra, amethyst, Isatidis, Salvia.

(3) and yin deficiency type:

syndrome: multi-stage or chronic sequelae to see the type. Symptoms: palpitations, palpitation, shortness of breath, chest tightness, fatigue, pale

[Examine]

sinoatrial block which checks should be done?

is no relevant information.

rely mainly on the ecg diagnosis. sinoatrial block was based on ecg characteristics can be divided, second, height, three sinoatrial block.

1. sinoatrial block was once sinoatrial block refers to the sinus node conduction time Zhixin room extension. As the sinus node potential is too small can not be displayed on the ECG, sinoatrial conduction time and naturally can not be measured. Only once to capture the sinoatrial block suddenly disappeared the moment the diagnosis is possible. In the following two cases may be diagnosed.

(1) once sinoatrial block and second degree sinoatrial block exist, in some cases can make a diagnosis on the electrocardiogram. It features a set of sinus rhythm without sinus arrhythmia occurs after a long interval. Than a sinus cycle length, and shorter than two sinus cycles (that is less than the normal sinus cycle intermittent 2-fold), as can be inferred in front of a long interval of normal sinus rhythm of sinoatrial block was , no sinus P wave length interval for the second time sinoatrial block.

(2) When they find the long time interval after a long interval exists, while the second long interval lengthened sinus cycle interval is equal to three times, once can be diagnosed as sinoatrial block. Based on this point with sinus arrest, sinus arrhythmia, not downstream atrial contraction decisively separated, so that once the diagnosis of sinoatrial conduction block is more reliable.

2. second degree sinoatrial block

(1) second degree sinoatrial block type Ⅰ: second type Ⅰ sinoatrial block, also known as Wenckebach second degree sinoatrial block or sinus period of increasing type room sinoatrial block. sinus room period (SP interval) is the sinus node (S), excitement spread through the sinoatrial transition zone surrounding atrial muscle (P) of the time, also known as the sinoatrial conduction time (SP conduction time). However, the conduction of sinoatrial transition zone, not as atrioventricular block with PR interval for reference, while the second typesinoatrial block can only rely on the change of pp interval analysis.

second typesinoatrial block based on the changes of pp interval can be divided into three types, namely a typical venturi-type, variant venturi-type, atypical Venturi type.

① typical venturi type sinoatrial block: also known as Okada Ⅰ type sinoatrial block.

A. The mechanism: the excitement of the next issue of the sinus node transfer process, the conduction velocity was progressively slowed down until completely block can not be passed atrium, which is a function of the gradual decay of the conductivity performance. Department of sinoatrial transition may also be areas of relative and absolute refractory period refractory period pathologic extension, especially the relative refractory period extension caused by pathologic. This phenomenon appeared again and again.

B. ecg characteristics: a. must be in sinus rhythm, sinus P wave. b. There are pp interval gradually shortened and then appeared a long pp interval, and again and again. c. long pp interval is less than the minimum pp interval of 2 times (Figure 1).

appear in the rules of the second typesinus rhythm sinoatrial block, each of its cycle regularity is very easy to identify, but in most there are different degrees of sinus rhythm missing, it increases the block cycle diagnostic difficulties.

In practice, elongated face pp intervals, short, shorter, the longest regular changes, follow these steps to the analysis (Figure 2):

a. measuring a block period of time: two consecutive block periods (long pp interval) after a distance from the sinus P wave. This limit cycle in each block should be equal to or a multiple relationship.

b. measuring a block cycle, the shortest distance from the pp interval.

c. pp interval with the shortest period of time from the removal of block: This block is reached within the sinus cycle, number of cycles (such as a decimal, then the binary integer).

d. c derived from the number of cycles in sinus cycle arrest subtracting a known number of pp intervals: the interval is equal to the number of pp off.

e. obtained with c in the number of cycles to remove a sinus block cycle time: a sinus cycle is equal to the spacing.

② variant venturi sinoatrial block: also known as Okada Ⅱ type sinoatrial block.

A. The mechanism: Man's cycle, the sinoatrial conduction time (SP conduction time) gradually extended, and sinoatrial interval increments gradually decrease in sinus excitement can not be passed before the next increment actually increased. The reason is due to sinus excitement in the process of downward conduction, retrograde place, concealed conduction, causing the subsequent sinus excited sinoatrial unexpectedly extended.

B. ecg characteristics: a. must be in sinus rhythm, sinus P wave. b. sinus pp interval gradually shortened pp interval followed by the same or slightly longer. Finally, the emergence of a sinus P wave without a long interval. c. no sinus P wave length interval: the long pp interval slightly shorter than two sinus cycles (Figure 3).

③ not typical venturi type sinoatrial block: also known as Okada Ⅲ type of sinoatrial block.

that there is no typical venturi type sinoatrial block, sinoatrial increment is not decreased, and gradually increased. On the performance of the ecg pp interval gradually extended, and then suddenly was prolonged into a sinus P wave without a long interval, long interval slightly shorter than two sinus cycles.

second type Ⅰ sinoatrial stroke due to atrial leak, so the proportion of non-sinus atrial conduction was 1:1. And the second type Ⅱ sinoatrial block, as can be in various proportions was conducted. For example: 3:2,4:3,5:4, can form a "bigeminy" "triple law," and so on, or was 2:1, 3:1, etc., can be expressed as sinus bradycardia.

second degree sinoatrial block type Ⅰ showed 3:2 conduction characteristics: two consecutive long pp interval and is equal to three consecutive short pp period between the sum that the P4P5 + P5P6 = P1-P2 + P2-P3 + P3-P4, or P1-P4 = P4-P6. Such laws appear in the ecg with a number of the more greater diagnostic reliability. When it occurs when the continuous performance for a variety of alternating short and long pp interval.

repeated venturi-type 3:2 sinoatrial block and second degree sinoatrial block type Ⅱ identification point: the former are gradually shortened pp interval phenomenon, and cycle characteristics; and the latter a long interval before the pp interval equal.

(2) type Ⅱ second degree sinoatrial block:

① the mechanism: second degree sinoatrial sinoatrial block is due to the transition zone of relative refractory period and the absolute refractory period extension caused by pathological, type Ⅰ second degree sinoatrial block previously dominated, while the second typesinoatrial block is mainly the latter dominated, so excited can not pass a single sinus atrium. Second type Ⅱ sinoatrial block: a conduction ratio of regular (ie fixed) and the proportion of irregular conduction of two types.

② common conduction ratio of regular (ie fixed) type Ⅱ second degree sinoatrial block:

A .2:1 second conduction type Ⅱ sinoatrial block: a more rare, the electrocardiogram showed regular continuous conduction ratio of each sinus P wave leakage after stroke once atrial (sinoatrial block that occurs once), was 2:1 conduction. When the heart rate is slow (30 ~ 40 times / min), the performance of like sinus bradycardia, sinus node, if not direct tracings potential, it is difficult to distinguish between the two. When physical activity or injection of atropine, sinoatrial improvement can be converted to 1:1 conduction, heart rate suddenly doubled, can be diagnosed as the second conductive type Ⅱ 2:1 sinoatrial block.

B.3: 2 or 4:3 or 5:4 ratio, etc. remain the same second conductive type Ⅱ sinoatrial block: that is, every 2 or three or four times a sinus beat occurred sinoatrial block. ecg showed 2 or 3 or 4 sinus P wave resulting from a leaking pump, no P-QRS-T wave group, the long interval between the pp just for a short period of 2 times. sinus beats between the P-P interval equal.

C. regularity of the second typesinoatrial block of ecg characteristics: a. sinus P wave. b. Rules of the pp period between the sudden appearance of a long interval, during which no P-QRS-T wave group. c. Rules of the subsequent pp interval between the long interval was fixed ratio: 2:1 or 3:2 or as 4:3 or 5:4, etc. (Figure 4). d. long pp interval is shorter pp interval of integer multiples, commonly 2 times.

③ irregular proportion of the second conductivity typesinoatrial block in a series of ecg showed sinus arrhythmia, the sudden appearance of a sinus P wave without a long interval, long interval and pp interval cycle appropriate for the sinus pp interval of 2 times. The transmission ratio is not fixed, can be presented 2:1,3:2 or 4:3 and so on. Diagnosis should indicate the transmission ratio. See more of this type (Figure 5).

(3) second degree sinoatrial block type Ⅲ: type Ⅲ second degree sinoatrial block Department of sinoatrial interval unshaped Ⅱ degree sinoatrial block.

ecg characteristics for varying pp interval shown, similar to sinus arrhythmia. Such as type Ⅰ and second alternating or intermittent sinoatrial block appeared even more support for second degree sinoatrial block type Ⅲ.

3. sinoatrial block height is 2 or more than 2 can not pass in atrial sinus excitement.

(1) ecg characteristics:

① in sinus rhythm suddenly long pp interval, exactly equal to short pp interval three times, four times or five times, etc., can be diagnosed as 3:1,4:1,5:1 respectively sinoatrial block, or collectively referred to as a high degree sinoatrial block. Diagnosis should indicate conduction ratio.

sinoatrial block in the highly conductive when the ratio can be constant, for example, are 3:1 conduction, conduction ratio can also be a few exist, so were noted in the diagnosis should be the minimum and maximum conduction ratio.

③ As the height of sinoatrial block is moved more than two can not pass in atrial sinus, can cause cardiac arrest longer, so in normal circumstances would have a escape or escape rhythm. If the atrioventricular junctions of escape, escape is easier to form - won by heart and repeated beating heart.

4. three-degree sinoatrial block (complete sinoatrial block) is the excitement all in sinus sinoatrial transition zone can not be blocked downstream. ecg Features:

(1) sinus P wave disappeared completely, it is difficult to identify with sinus arrest, sometimes both co-exist.

(2) At this point the basic rhythm of the heart than from the point of issue of ectopic rhythm, emotional control of the heart. For example, the transition zone atrioventricular or ventricular arrhythmia own rhythm. If atrial escape rhythm is helpful for three-degree sinoatrial block diagnosis.

(3) can sometimes be indirectly confirmed by the atropine test: After intravenous injection of atropine into second sinoatrial block can make a diagnosis.

5. second degree sinoatrial block typesinoatrial block the merger was second typesinoatrial block after block in the event of a complete. Sinoatrial transition area to rest and make it as functional improvement. The original was sinoatrial block sinus excited sinoatrial transition zone through time. The second type Ⅱ simple sinoatrial block-long pp interval shorter pp interval is equal to 2 times; once the merger sinoatrial block, then the length of the pp interval is shorter than twice the pp interval , can be diagnosed as type Ⅱ second degree sinoatrial block sinoatrial block once the merger.

second typesinoatrial block sinoatrial block once the merger, because the text's phenomenon, itself a long pp interval is shorter than twice the pp interval period, so the second time in a venturi-type type Ⅰ sinoatrial block, difficult to diagnose whether the merger was sinoatrial block.

[Diff]

sinoatrial block and the diseases easily confused?

1. second typesinoatrial block and sinus arrhythmia identification venturi type of mutation type sinoatrial block of varying duration between the pp sometimes difficult to be differentiated with sinus arrhythmia. Based on the following points can be used for identification:

(1) must be calculated using a Venturi cycle of sinus excitement cycle: the cycle of the ecg with the leads appear Wenckebach cycle similar to the pp time to draw the ladder results are generally in line with diagnosed before they can diagnose this type of sinoatrial block.

(2) Wenckebach cycle again and again.

(3) sinus arrhythmia and breathing when the pp interval, was gradually reduced and gradually extended features. And this type of block pp interval there is a certain change in the law, is gradually reduced and finally once in nearly 2 times the short pp interval between the long term.

2. second degree sinoatrial block type Ⅱ second type Ⅰ with 3:2 sinoatrial block was the identification of both short and long pp interval the alternating pp interval, but second type Ⅰ 3:2 sinoatrial block long-short pp interval is less than 2 times the pp interval; the second type Ⅱ 3:2 sinoatrial block length The pp interval is shorter pp interval multiple of 2 times.

3. Ⅱ type second degree sinoatrial block and sinus contraction bigeminy identification of sinus contraction bigeminy is not a short-long pp interval pp interval of 2 times. The second 3:2 sinoatrial block type Ⅱ long intermittent sinus pp interval of exactly 2 times the pp interval.

4. Ⅲ type second degree sinoatrial block and sinus arrhythmia identification of the different points of second degree sinoatrial blocktype of the pp interval suddenly shortening, suddenly extended, has nothing to do with the respiratory cycle. The sinus arrhythmia is when the pp interval gradually shortened, and gradually extended, with the respiratory cycle, breathing short, long exhale.

5. sinoatrial block with a high degree of sinus arrest sinus arrest identified no significant general rule, the length of pp interval does not exist multiple relations, and in a ecg in the period between arrest rarely equal to sinus arrest. In the height of sinoatrial block, regardless of the degree of block, long pp interval shorter pp interval is always integer multiples. And, its length equal to the long pp interval can be recurring. sinus arrest rhythm, often low point was also inhibited, in general, less prone to escape. In the height of sinoatrial block, cardiac arrest for too long, often prone to atrioventricular junctions of escape and escape rhythm or ventricular escape ventricular escape rhythm.

6. three-degree sinoatrial block and sinus arrest lasting identification of sinoatrial block three times with atrial escape or escape rhythm stroke; sinus arrest more non-atrial escape or escape rhythm, sinus node is the suppression of self-regulation of pathological factors, while inhibition of the atrial ectopic pacemaker. But atrial escape rhythm were not necessarily sinoatrial block. sinoatrial block are not necessarily appear atrial escape rhythm, then it is very difficult to identify. Or in Holter ecg monitoring, if the P wave not seen in a long time before there had been temporary or more long sinus arrest, may be diagnosed as sinus arrest; if there had been one, second degree sinoatrial block, can be diagnosed with three sinoatrial block.

7. three-degree sinoatrial block sinus ventricular conduction with the identification of the following points:

(1 ) sinoatrial block may have atrial escape rhythm, the latter does not.

(2) sinoatrial to atrioventricular block transition area more than the basic rhythm of the heart, so much for the room on the qrs wave, while the latter are mostly large malformations.

(3) the latter is often accompanied by hyperkalemia-induced T-wave high-angle, while the former does not.

(4) If blood potassium increased, or clinical cause hyperkalemia can be discerned the presence of the disease, is often the formation of diffuse room block caused complete sinus ventricular conduction, and less impact on the sinus node.

[Disease]

sinoatrial block may be caused by the diseases?

sinoatrial block-related diseases

myocardial infarction, atrial sinus rhythm disorders in children non-paroxysmal sinus tachycardia arrhythmia in acute myocardial infarction in children with neonatal arrhythmia arrhythmogenic right ventricular cardiomyopathy in children with sinus tachycardia sinus bradycardia in children with periodic hyperkalemic paralysis in children with cardiac arrhythmias in children myocardial infarction, sinus contraction coronary sinus bradycardia, sinus disorders arrhythmogenic right ventricular cardiomyopathy, sinus tachycardia

more chest symptoms

"multi-temperament" heart sounds "butterfly" shadow co2 retention pas staining large abnormal qrs wave QT interval prolongation t wave flat or inverted one hundred specific symptoms of valvular thickening of valve leaflets thickening after satiation chest crackles gallop heart sounds allergic cough pathological q waves with atypical chest pain does not complete the room block side rib pain, unstable angina stitch


小黑屋|Archiver|Healthcare | | 有健康網

GMT+8, 2014-10-22 16:02 , Processed in 0.368931 second(s), 2 queries , Gzip On, Memcache On.

Powered by Discuz! X3.1

© 2001-2013 Comsenz Inc.

Top