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This heart’s geography’s map—this limitless small continent—this soundless sea…
-Walt Whitman

First of all, let’s get all the Latin and cursing out of the way with right at the start. SVT is supraventricular tachycardia which is Latin for Fucking Fast Heartbeat. There!

In my case, my heart clocked in at 238 on September 9, 2015, sometime after five in the evening after five and one-half miles of a planned sixteen-mile run, just as I was beginning to ascend ball bearing. I was running with a heart rate monitor that would do an electrocardiogram (ECG) in case this very thing happened. It was a hot day – probably 95 when I started my run at Quarry parking lot near Auburn. My hydration pack was filled with ice. The moment I felt my heart rate spike from 130 to 238, I pressed the transmit button which sent my ECG to somewhere in Florida, then back to California, and I sat down to concentrate on breathing.

I imagine people experience SVT in different ways. For me, there is a brief instant just before tachycardia when I know – a feeling of what I later learned is a sort of skip in the heart beat preceding a beat so fast that my brain loses oxygen and I begin to feel light headed. An event in medical parlance. So I sat down to breathe…now that I knew. What I knew was that I didn’t want to pass out at the base of ball bearing at that moment.

IMG_0518

Near the base of Ball Bearing (Maine Bar Trail).

Here is how my medical team reported the event:

Cardiology was notified of your event and it showed a supraventricular tachycardia. They recommend you be evaluated further by our cardiac electrophysiology specialists to discuss the best treatment options for you.

Specifically, my diagnosis was AV Nodal Reentrant Tachycardia (AVNRT), the most common type. Essentially, this is an electrical short circuit near the center of the heart.

The heart has a natural pacemaker called the sinoatrial node (SA node) which kicks off this wondrous sequence of events that is the heartbeat (your pulse is simply the number of signals the SA node generates each minute). Starting near the top of the heart, this spark of life begins at the right atrium and travels down along electrically conducting pathways.

cardiac-conduction-systemThe first signal tells the heart to contract and pump blood. Electricity then flows along two pathways (the fast and slow pathways) to the AV node, where there is a slight pause to allow the right and left ventricles to fill with blood. It is here that an extra pathway may cause the signal to loop in a circle (the reentrant in AVNRT) and override the SA node’s normal pace-making duties, greatly speeding up the heartbeat in the process.

AV_reentry_circuit

The reentry circuit – AV node

So, one week later, I was patched into an IV and getting hooked up to all kinds of wires, after having undergone various blood tests and electrocardiograms, in preparation for a radio-frequency catheter ablation of my heart. What you should keep in mind, is that SVT is not considered a disease of the heart and is usually not life threatening. And neither is it caused by running. Although in my case, running triggered SVT. Other triggers can include caffeine, antihistamines and stress. But the underlying cause is an unknown abnormal electrical circuit.

Toward the unknown region…

April 11
During runs earlier in the year, symptoms sometimes presented as difficulty breathing and tightness in the throat. As I was in the midst of allergy season, this was what I naturally thought of as the cause. It even seemed that a bad day at Lake Sonoma on April 11 might have been down to having received the second of three doses of the rabies vaccine the day before (another tale). “Headache, nausea, abdominal pain, muscle aches, dizziness,” are the possible mild problems associated with this vaccine. Yet they are also indistinguishable from the “mild problems” associated with running an ultra marathon. But in retrospect….

Lake-Sonoma

At Lake Sonoma 50 – photo by John Evans

There was a moment during Lake Sonoma around mile thirty-five when I could not take another step. A tightness in my throat (a symptom of SVT) made breathing difficult, so I sat for a moment. I am going to have to drop, I thought. But to do so, I had to get to the next aid station at Warm Springs Creek, three miles distant. No one could help me get there. So I dumped everything left in my pack into my body. This consisted of two packets of Scratch, two GUs and some Endurolyte tablets. Minutes later, I was moving again and feeling optimistic. Thoughts of dropping were gone.

But wait…weren’t you wearing the heart rate monitor that came with your Garmin? A good question, to which my answer is…no. It took a run on May 28 on Quarry Trail when my throat tightened up and I had to stop short at Brown’s Bar that made me think I should strap the bugger on again. And then nothing happened, until June 16 on a run from the Overlook just before starting up K2.

I stopped to catch my breath, which was short and rapid, and glanced down at my Garmin. It read 235 bpm. Well that’s my max…hold on, isn’t it that less your age? Must be something wrong with the watch! I later saw that my heart rate was 235 for four minutes that day.

There followed three other events: June 23rd, 226 bpm for five minutes; August 23rd, 230 bpm for nine minutes; and August 24th, 233 bpm for seven minutes.

When I met with my primary care physician, I expressed concern since I was planning on running Rio Del Lago on November 7. “Well then, we better figure out what’s going on,” was her response, and she gave me a heart rate monitor to wear for thirty-days.

Since I was wearing only the Kaiser provided heart rate monitor during the pivotal event on September 9, I can’t tell you how long I sustained a rate of 238 bpm. It was probably around nine minutes. I had trashed my Fenix 2 the week before taking what Bob Halpenny called a most spectacular fall which gave new meaning to Garmin’s metric “ground contact time.” Thankfully, x-rays confirmed nothing was broken except the Fenix 2. My doctor, no doubt, was wondering what I was up to again and gave me what I considered to be sound medical advice…“don’t fall.”

waves-of-the-ecg

Normal ECG waves.

Which takes us to September 16 and the cardiac ablation…

The map of my heart…

September 16
Before the ablation, there is the electrophysiology (EP) study. Since heart tissue will be destroyed during an ablation, it is nice to know that nothing critical is being zapped, which might result in implantation of a pacemaker. The EP study is the process that maps the electrical pathways of the heart, and points to the precise spot of the abnormal circuit.

Access to the heart is gained from an artery or vein near the groin (good grief!). Since I must remain awake during the procedure, something special is dripped into my IV to keep me calm. Conscious sedation is the medical term. Which works well. In order to get the catheter into the artery (think of a plastic tube not unlike spaghetti), some lidocaine is used as local aesthetic. After this, I feel more like an observer than a participant.

The tachycardia must be triggered to identify my aberrant circuit. My heart is now in my doctor’s hands. He controls its beating – as like a switch he effortlessly turns on and off. Painlessly, I feel my heart being fiddled with, speeding up and slowing down, as my electrical circuits are mapped. At one point, my heart feels like it is trying to leap out of my chest. “That’s nice,” I think, without a bit of concern. Then some ablations begin which I sometimes feel as warmth in my chest. Afterwards, for sometime, I will occasionally feel as if someone has the barbeque on when I take a deep breath. After two-hours, the procedure is done. Several spots were ablated.

normal-sinus-rhythm

Normal sinus rhythm from 12 lead ECG.

Recovery takes four hours. My doctor turns my heart from his hands into the hands of my nurses. Poetry is insufficient to describe their care. I know, because I have searched for some to use in this piece, and the words always fall short of what I feel. Nursing is one of the noblest pursuits. A major complication during recovery is bleeding from the puncture sites in the groin (good grief again!). But I am well looked after, and there are no complications.

This precious heart set in the silver sea…

September 24
One week later, I laced up my Altra’s to take my first post ablation run. The first mile was good, but there followed a skip, and my heart rate instantly spiked to 220 bpm. Pressing briefly on my femoral artery, I was able to bring the heart rate down and walked home – feeling blown about like the fall leaves that swirled in the warm Sacramento breeze. That was the moment I knew I should drop from Rio Del Lago.

After another consultation with my cardiologist, we both felt it was worthwhile to go back into my heart and take another look around. He doesn’t like to be too aggressive when he does these procedures. There is no line over which he can backup if he goes too far. He had ablated about one-dozen spots in my case, which is quite a lot. I have a stubborn heart, he noted. So, the usual blood tests were ordered and another date set.

You again…

October 7
Glenda and Jack instantly recognized me when I walked into the Cath Lab. We proceeded to have a grand time – like old friends. The preparation and electrophysiology study were done as before, although the procedure took longer at two and one-half hours.

My doctor accessed my heart from arteries on both sides of the groin this time (good fucking grief!). Despite this, I felt more relaxed in recovery. My pulse was hovering in the 60s, and somewhat tired, I took a yawn. My heart rate leapt to 120, and the alarms started ringing.

Oddly, every time I took a deep breath, my heart rate jumped, sometimes up to 130. A 12-lead ECG was ordered, but the rhythm on the monitors looked different from that of supraventricular tachycardia. The doctor said he ablated quite a few spots for a total of nine minutes of burn time. At one point, he said he didn’t think he could do anymore without risking a pacemaker. In my consciously sedated state I thought “hmm…” But then he took another look and zapped a few more bits after which he was unable to induce tachycardia.

The general consensus was that after two ablations close in succession, my heart was essentially saying WTF (latin again)! A stress test on the treadmill was scheduled, and I was temporarily prescribed some heart medication.

October 13
Although it was no Goat Hill, the stress test did get my heart pumping. Strapped into all sorts of wires again, and with a blood pressure cuff on my arm, the treadmill gradually increased its speed and slope. Thankfully, the technicians were unable to induce SVT. Although I did have palpitations and some skips in the heart beat originating in the atrium. These may be a result of bruising and swelling from the procedure and should subside. Looking over the before ablation and after ablation ECGs with my doctor, he pointed out that these skips were happening before the first ablation.

October 20
It was not without some trepidation that I went on my first run following my second ablation today. At the start, my heart rate jumped to 150, and you probably have a good idea what I thought…I stopped and walked whenever it spiked. But after three-quarters of a mile, as I deepened and slowed my breathing, it started to stay below 130 in my aerobic range. I still experienced palpitations, but I managed four miles, which was all I set out to do. In two weeks, I’ll take another heart rate monitor from Kaiser out for a spin, and we’ll see if the ECG has calmed down.

Until then, keep the trails warm for me. I have big plans for 2016 which include a 100-miler. The trails and ultra community are lodged deep within the map of my heart.

Supraventricular-tachycardiaSaint-Exupéry was a pilot in the early days of aviation. He was also an author. Although he was writing about flying, to me, this quote captures an important reason to run “…it releases my mind from the tyranny of petty things.”

Heart and ECG graphics are courtesy Life in the Fast Lane.